Hi,
I have the same problem (the Alembic is from Blender 2.93).
When I import the Alembic and create the binding everything is fine… but when I set the groom component to the blueprint of the third person dummy, the hair has a strange offset and only after a restart of the UE editor (version 4.27.2), the hair is in the right position.
Then there’s the physics problem. Activating the default preset creates strange interactions and glitches. I’ve changed the Niagara solver from Groom Spings to Groom Rods and the simulation has improved but the interpenetrations and weird hair stretching when walking or running remained.
Have you made any improvements since you published the post or found any other solutions?
I followed this tutorial but it’s almost a year old.
https://www.youtube.com/watch?v=Y5XjRxbwI7A
I attach my test.