I figured that was the case, but what I meant was what settings did you use when retargetting? =)
Can you show your retarget manager settings?
The only other thing I can think of is you may have unchecked the convert scene box when importing your custom character into UE4 which converts the up axis to Z+ rather than Y+ which could have messed the orientation up when retargetting. UE4 characters use Z as the up axis rather than Y which is typical in modeling programs.
I’m also going to assume this is only happening when animations are being used? Does the Skeletal Mesh display this issue as well?