The mirroring x axis is broken.
I think it has to do with epic (or somewhere during the porting process) setting bone roll values. I made a video 9 months ago on how to fix this issue, but it seems as though it has not been fixed with the new version of porting.
I don't know how hard it will be to fix it, but if you need any additional information on how I fixed it, I'll be happy to link the video (I saw "no self promo", so I won't link it unless asked) or outline the steps I took to fix it.
#Fix axis mirror
stiff gale
worn stream
Doing that will break emotes
stiff gale
Ohh, I see