Somewhere in your post is a typo, the question is where?
If you've got an FAA PPL then, subject to having differences training for microlights signed off in your logbook by a microlight FI then yes, you can fly UK microlights on an FAA PPL(SEL). And yes, you can log PiC, but you will still need to have a current FAA medical and BFR.
If it's a USUA-PPC certificate, then no, you'll need to do an NPPL(microlights).
G