Do I have to back this up?
It starts with them fighting over Bucky, then Sam begrudgingly accepting Zemo's fashion advice, and then a candlelit dinner to German classical music, until Bucky finds them on the sofa, and Sam's all "Yeah I'm kissing the Baron, let's not make a big deal out of it."
"There's a bit of green in the blue of your eyes," "I've studied you,"
But why, Zemo? Of all the Avengers you could have amazing chemistry with. Like....
Mostly because of their incredible actors. I'll die mad they never shared a screen together in the MCU. The angst would be marvelous. Two sugar daddies competing for dominence while mourning their families and hating Steve Rogers.
The vengeful power couple. Zemo doesn't seduce Sharon though; she just straight up joins him, cuz she's that fed up with the Avengers and the government.
Zemo gets more than he bargained for when he tries to fuck with Asgard the way he did the Avengers. The Trickster God might give this manipulative Sokovian a taste of his own medicine.
Two manipulative Sokovians who blame Tony Stark for their dead families. Maybe the Baron takes Wanda off the streets, and makes her his bride or mistress....not expecting her to end up overpowering him in every way. The Scarlet Baroness may take over her husband's empire.
(We'll presume Wanda's an adult for all this. Unless you want to get deliberately creepy.)