Costa has got some decent grappling, on the other hand idk much about his offensive wrestling since we barely see him use it.
If he mixes it up he could get a win since it'll open up the striking due to the takedown threat and Pereira doesn't always have the best defense on the feet so Costa could get some decent success if he uses all his tools.
However, if he just stands with Pereira and he might since Costa doesn't always have the smartest approach then Costa going to get flatlined.
Dude's way too flat footed and very hittable, Poatan would pick him apart or just catch him coming in.