I actually think that her costume will be designed to work well with Ant Man, and vise versa. So I can see her, like him, having some sort of silver-ish helmet perhaps like that Ultimate take on the classic Wasp costume with the pointy helmet. And like Ant Man I think she could end up with a mask that ends up covering her whole face in some scenes. I mean it would fit with her flying, they could work it that she needs an air supply while flying really fast, needs goggles to help her see and to cut down on the pressure on her eyes, the pint would be for aerodynamics. Plus her power, similar to Ant Man's, come from Pym Particles right? Something she, and he, breath in to make themselves small. So the masks would make sense for that too. Stuff like that. But I think she and Ant Man will have similar designs to their costumes. Not saying they will be like X-Men in matching black leather outfits, but have similar designs like War Machine to Iron Man or the Warriors Three and Loki and Odin to Thor.
I see them combining the Ultimate and the regular 616 version and maybe the classic original version as well. I may draw something up for fun.
This was my idea for the Ant Man movie costume: