Stretch additive for 50/50 polyester/PBT swimsuits

[IntegrityShirts]

First off, as far as I can tell, PBT is some sort of polyester fiberglass concoction that I have no clue whether I can even print.  Has anyone printed on this material? I believe these are Nike suits. For collegiate athletes so some sort of performance thin suit for ladies.

Should I use a stretch additive and regular plastistol inks? Should I mix the additive in each color or do a stretch base, regular plastisol on top?

[Frog]

Nike probably has someone who can advise on this fabric

[IntegrityShirts]

Could also be Speedo suits. Further searching looks like it's a form of polyester with 4 way stretch. PBT stands for polybutylene terephthalate, oooo phthalates yum!