Kissmehameha

I'd imagine Goku would do this after returning from the Goku Black fight.

He'd remember what Vegeta said and what Future Trunks did. After calling for his wife, Goku would look at Chi-Chi, first appreciating that she was here (remember Zamasu told him he killed his timeline's Chi-Chi), then he would bend down to her height and kiss her. As this would be his first time kissing, it's likely that it would be a sloppy kiss, but Chi-Chi would be both shocked that her husband, her Goku, would do this so suddenly (where did he learn this from??), but also because she really liked it, even if it was an amateur kiss.