While on the topic of meeting their counterparts
How would the animasks react to meeting the PJ masks
If the AniMasks aren't doing anything too mischievous, then I think they'd passively interact with the PJs. Expect ALOT of teasing and comparisons between the two teams
Night Panther would immediately try to race Catboy, & Dark Owl wouldn't mind having someone else to talk to about Flossy Flash (Even if she DID steal the comics. Owelette was easy enough to convince to read it anyways)
Out of the three, I think Gekko would be the one most uneasy being around the AniMasks. He IS the one with first hand experience in dealing with his version of Night Panther & Dark Owl, but Gator is pleasant enough to be with.
—But if the PJs ever get in the way of whatever thing or mission the AniMasks are up to, then they would absolutely use force.
Lmaooo I just like the idea that the Masks and the PJs met because of Space Fairies shenanigans, so have an early peek at Villains AU Lily Fay. (It's also an excuse to draw them)
However, the Space Fairies being directly involved with AU Shenanigans is not canon here. (-but it IS possible) Also they would know that it's dangerous bringing people between universes.
(Do NOT travel through alternate universes with Space Fairies alone. You WILL get explode travelling through space without safety.)
If I wanted to have the PJs and the Masks actually meet together, I would work it into the story like maybe through Romeo's tech, some kind of ancient spell, or some other third thing?