When the Blender path works, you could make your rigged character with a short idle animation the template file.
Then export with other moves but export to .usda.
Then create a new file that references the template/master and over the animation related attributes, copied from the above mentioned .usda
This way, you get a library of animations all re-using/referencing the same character (that can be modded)
But that goes deep down the TD rabbit hole.