Feet floating with retargeted animation

[MalachiDraven]

I retargeted some animations from UE4 Mannequin to G8 and the feet are floating and move a bit more than they should be. It almost looks like the IK stuff isn't keeping them to the floor. Same thing happens if I retarget from UE4 to UE5 mannequin and then to G8 too.

Any idea what's causing this or how to fix it?

Edit: The feet also slide whenever the hips shake, like when dancing. They don't do any of this on the UE4 or UE5 mannequins.