Scarlet Witch
Since there are so many more male characters in the MCU than female, inevitably the female characters will have to be involved in more relationships. Since the Vision (who Wanda Maximoff has a long history with in the comics) will probably lose something very close to him in the next couple of years, who do you think she will be involved with next? She has history with Dr. Strange in the comics, so in a post Infinity War world she might become his apprentice.
I really don't like Black Widow and Bruce being an item. But maybe other people like it. I won't ship her.
Captain Marvel? Her and War Machine had a thing in the comics(until Thanos killed him. Spoiler!), but I don't think Brie Larsen and Don Cheadle will be matched up. Maybe Thor? She's similar in power level and Jane's gone.
There's always free cheddar in the mousetrap