Malevolence

Well based on the just leaked wondercon footage, so kindly provided by SPACEGODZILLA2, I believe they won't! They just appeared to roam and behave like other animals would if they were that size, if you get what i mean. The muto wasn't even overly agressive when challenging godzilla.

I think they have characteristics like the Xenomorphs from Aliens. It is all natural to them, they don't mean to cause harm, it is just their instinct. :)

Hard to say. These guys definitely have a bigger problem with those pesky little ants called "humans", though. Godzilla seems to only retaliate when he notices us touching him in a significant manner. Which means lots of missiles and bombs and whatnot before we get an angry glare. But these guys clearly don't wanna even look at us! These Mutos appear to actively seek out and destroy any humans they can, though it seems that overall, they're like a really, really, REALLY big animal.

They'll probably act like normal animals, running on instinct and some level of sentience. But if Godzilla and Muto are indeed creatures from the same time period, they might recognize each other as natural enemies and have some ancient memory kick in to boost their instinct and start to fight.

I'm guessing they might just be really agressive predators. The only reason why the winged Muto didn't try to outright attack Roidzilla is because, well, he's a BEAST. The size difference alone is something common in our animal kingdom where we see larger creatures intimidating smaller ones in one on one stand offs. I imagine the Muto is smart enough to know not to run up on it lol. He might get ROFL stomped in front of everybody and that would just be embarrassing for him.

Also, milady, If I may interject, The first synposis that came out also says that these creatures would be bolstered by man's "Scientific Arrogance". What if in the film, we enhance them in someway that makes them malevolent?