(Deleted old Reply because it was inaccurate)
Posting here just to let anyone who runs into this issue in the future
If you want multiple limbs/Profiles to be simulated without your bones snapping to the root, you MUST do the following:
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This is the critical part that took forever to figure out: In Blender, you need to make sure your units are set to metric 0.01 (if you have to change your units to 0.01 it will change the size of everything when you import, so its best to scale it back up before the following steps) , your armature and every bone is named something other than Root or Armature, and make sure all transforms have been applied to your mesh and skeleton (this is the most important part); This will most likely break any animation you have, so you will need to scale the Locations (specifically only the locations) of all keys in your animation to the scale your Armature was originally scaled to (only in the y axis)
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You will have to delete your skeleton file from UE4/5 before importing the corrected skeleton and animations (you cant reimport skeletons)
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When importing to UE4/5, do not import at any scale other than 1.0
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You can verify this is fixed by checking all of your bones in your skeleton in editor are scaled to 1.0 (or ~.99999999 because floats)
You should be able to simulate multiple chains of bones from there
Let me know if anything is unclear, I have confirmed this time the above is the correct way to fix this issue by having a broken skeleton become a fully working multi-simulating skeleton.
Hope this helps a few people!