No problem @TrevorDwyer let see if we can get to the bottom of this so that you can continue to work on your project 
If you don’t mind, we’ll be taking this step by step. I will be providing you with how I’m setting up my project on my end and the steps I’m taking to re-target animations to make sure we are taking similar steps that way if something breaks I can go back on my end or ask you to check a specific part. I’m assuming that you already know how to set up your project to work with Metahumans since I can see that you are using one from your image so I will skip that part. During this process if my assumptions are wrong or you get stuck in any steps please let me know and I’ll be happy to help. Okay with that out of the way Let’s get to the fun part 
Project Settings
Engine Version: UE 5.6.1 (these steps should also work with 5.7 and 5.8)
I’m starting a brand new project, I’m using the “Third Person” template and under “Variant” I’m using “all” just in case I need the resources that come with those variants in the future as we try to figure out what is causing you problems. You do not have to choose all, choose accordingly based on your project needs 
Okay now that we are in the engine and the project is open, I’m just creating a metahuman and from the presets. For the purpose of this I’m removing the garment to be able to see the full body when I’m re-targeting the animations. If you want to do so as well, navigate to “Hair and Clothing” and double-click on the garment
Note: Make sure to enable the metahuman plugins to able to work and create them. And enable missing if you get the prompt to do so.
I’m just creating the rig and downloading the textures to be able to assemble the character. (this may take a few seconds)
- I’ll be using “UE Cine (Complete)” under the “Assembly” drop down menu
- using "UE (Optimize) should also work too
- I’ll keep the Root directory as default
- And I’m naming the character “MH_testChar_001” but you can name it however you’d like.
- I’m clicking on Assemble to assemble the character.
Note: If the option to assemble your character does not appear after downloading the textures and creating the rig. Try clicking on another tab in the metahuman editor such as “Hair & Textures” and then go back to Assembly, the option to Assemble should be available now.
We can now close or minimize the Metahuman editor and go to your Content Browser. If you look closely, you can see that a new folder has now been added “Metahumans” inside of it you will find a folder with the name you selected during the assembly set up.
Okay just to recap, we now have set up our metahuman, it has been assembled, and we know the location of the Blueprint.
Custom Interface: your interface layout may look different from mines. I have edited my interface so that you can see the following panels easier
- Details
- Outliner
- I’ve added a second Content Browser to the bottom of my screen
Custom Viewport:
Default Viewport
If you would like to edit your viewport to match mines you can:
select the Details Tab and drag it to the left side of the screen
Let’s add the content browsers, Window-> Content Browser-> Content Browser 1
Let’s add a 2nd Content Browser and drag it to the right side of the 1st one
Window → Content Browser → Content Browser 2
Let’s move the “Content Browser 2” window to the right side of “Content Browser 1” by dragging and dropping it there
We’ll re-orient the Outline by dragging and dropping the tab and making sure it lands on top of the upper right side of the “Content Browser 2”
To wrap it all up we can go ahead and resize the panels to your liking.
Retargeting the animations using project resources and external:
We will now cover how to retarget the animation using the resource from the variants we selected at the start of the project set-up. We’ll also cover using external animations, in this case Mixamo.
To keep things organized I’m going to create a folder to house our:
- External animations
- Retargeted MetaHuman animations
In All/Content/MetahumansI’m adding a MH_Anim folder (for Metahuman retargeted animations) and a Mix_Anim folder (for Mixamo’s animation)
Let’s start by using the Unreal Mannequin animations first. If you are having problems finding the animations in your project from the variant you choose, we can use the filter menu in the “Content Browsers”
Select the filter menu on “Content Browser 2” wile selecting “All” in your folder structure-> Select all filters → select Animation → Animation Sequence
This will now populate all of the animation sequences in the project.
I will be working with the “MM_” animations so I will type in in the search bar “MM_”, select MM_Attack_3 and use the keyboard shortcut “Ctrl+B” to go to the folder it’s in.
Right click the animation you would like to use, and select “Retarget Animations”
Once the Retarget Animations menu opens up, navigate to target skeletal mesh, and select your Metahuman’s Body mesh there.
Since I just want to retarget the MM_Attack animations I will just type “MM_Attack” in the search bar bellow and select all of the “MM_Attack animations”, if you would like to just retarget 1 then you can just choose one.
Note: if you want to see a preview of the animations to check that it won’t break you can just double click the animation you would like to preview and it will begin to play.
Let’s export the animations. With the animations selected, navigate to “Export Animations”, and select the folder we created to save the retargeted animations for our Metahuman character, I’ll name the prefix “Int_” for internal animations and click on export.
In Batch Export Options select import with the settings I have selected
And now in the Content Browser (in my case Content Browser 2) you will see the retargeted animations there
Let’s navigate to our Metahuman blueprint and drag and drop it in the level, rotate the metahuman blueprint in the level and re-orient your camera so that you can see the model better.
Now we can create a Level Sequence to test the animation.
I’ll create a Folder in /All/Game/MetaHumans and name it “Anim_Test”
Open the folder and create a Level Sequence, I’ll name it “Anim_Test_001”
Double click it to open it, your viewport may change to something similar to this, at the moment we are not going to be using those tabs so you can close them.
Let’s drag and drop our Metahuman blueprint in the level to the Level Sequencer timeline and delete the “MetaHuman_ControlRig” assigned to the Body by right clicking on top of it and selecting “Delete”
Now that the control rig has been removed we will now, go to Animation → Click on the plus sign next to it → add the animation we would like to test
let’s drag the animation to the last frame in our tikmeline so that we have more time to view the animation, click on “To Front” so that it takes us to the first frame and click on play to preview the full animation.
We will stop here for now so that you can check in with me once you’ve followed these steps to see if everything is going as it should on your end. If it is we will move to how to import external animations and retarget them. We will cover Live Link once we have both the internal and external animations running smoothly. Please do not enable it until then. I hope this is going well so far on your end and that it’s helping, please let me know if you come across any problems during these steps.