Why animations import rotation not working correcly

When im import animations in mixamo.
Checking in blender and rig is correct. but importing result is wrong way X = 90 degree.

When im import again and rotating animations X=90 degree. My result is 180 degree. why?
when im rotating x 89 degree. my result is 89 degree.

is this a bug.

Using UE4.15 with linux

This is somewhat known issue with Mixamo animations and UE4 in general not Linux related.

By the way, have you tried rotating -90 degrees? Just catching the straws here, did not try to import them yet. (There is/was a free mixamo pack in the marketplace that I downloaded in Windows VM and was using that ever since)