I'm having an issue when I uncheck Anim Rotation Only in the anim set. I'm doing this because if I don't the hip bone which is also my characters root bone will not animate causing their feet to slide back in forth instead of their hips.
In the anim editor the animations play fine. I also compressed the animations after I unchecked anim rotation only so I have no errors or warnings. I have also saved package after making all of these changes that didn't help either.
TLDR
However they look like this when they play in game.
Replies
That... Or the anim wasnt exported with the same skeleton size
Try checking the skeleton for scaling and set the scaled joints back to the value of 1, if you find them (again apart from the root). In case the skeleton was scaled in various places to fit the model:
In maya: Detach the model from the skeleton with "keep history" enabled. Select root -> select hierarchy -> freeze transformations. Rebind the model and export the fbx.
If you use any other software, you should be able to do similar, if not the same thing. But the important thing is to eliminate any redundant scaling.
Hope that helped.
edit: also another possibility is what Mrfred said. See if your default skelmesh has a different size compared to the skeleton in the AnimSet.