imported animation not correct


I was creating a T-Pose for the mannequin in order to be able to retarget my custom character. I found that there is something wierds going on when i import animations.

in 3dsmax i changed to this:

then, importing to UE does not change the legs:

It seems to be something with the base pose,… im not sure…

Anyone knows why any imported animation would be different from 3dsmax?