If you need any further guidance i have made a little guide for you, i have no clue on your experience or your current blueprint setup therefore i will cover it all.
Firstly i would setup my weapons using inheritance with a base class. Create a Blueprint Class → Actor. Name this "WeaponBase"
Inside of this blueprint is where you would add all of the things that every weapon would require, for example. Animations, Sounds, Mesh, Sights, damage, bullet range, fire rate, etc…
Set all of these variables “Instance Editable”
Add your mesh component, either Static mesh or Skeletal Mesh depending on your model. Then add a variable called “Fire Sound” type "Sound Base"
Then i would go into my “Event Graph” and create a Custom Event called “WeaponFire” i would then get a “Play Sound 2D” and attach my “Fire Sound” variable into the “Play Sound 2D”. Do not set the sound in the “WeaponBase” variable leave it empty.
Compile, save and close the blueprint class. Right-click on the “WeaponBase” and create a child actor name this to your weapon name, for example “Weapon_Name” Inside of the Child actor add all of your assets such as animation, sounds, Mesh, etc… and attach them to the variables that show up on the side, remember you are not creating new variables inside of the child actor your are settings them from the variables you made in “Weapon Base”
Go into your Character class and create a variable called “CurrentWeaponClass” type “WeaponBase” and set it as a Class Reference the purple ball, then create another variable called “CurrentWeapon” type “WeaponBase” set this one as an Object Reference, the light blue ball. Set the weapon you would like to fire as the variable for “CurrentWeaponClass” only classes that are linked to “WeaponBase” should appear including the child classes.
Finally add an input called “Fire” under action Mappings and bind it to any key the key set will be used to fire. Then get that input in your Character Class. I have added a picture of how to setup your character class for the fire.
This is the best way to setup a weapon it makes it very easy to create new weapons in a second plus it reduces the amount of code you will need.
If you have any questions feel free to ask i will try to answer them as best as i can.
I have included 4 pictures for extra guidance
I have noticed you are replicating this does not include networking but you can easily set that up yourself like you have done on your own pictures.