The “shake” effect is by rapid zooms. I’ll show you two old posts I saw years ago that showed the effect (on video and code). 
Uwe’s video:
https://www.instagram.com/p/BIaK02hgf2j/?igshid=1a5suocgbqa6m
Uwe’s code:
https://www.instagram.com/p/BIaRSR2AsYZ/?igshid=1qf0n68w5zito
For having the rapid zooms happen at the same time as the kiss, you’ll need to have &zoom on x y to % in s THEN zoom on x y to % in s THEN zoom on x y to % in s THEN zoom on x y to % in s
on a line before the kiss.
Uwe’s code works well for zone 1 (I know because I’ve tried it in zone 1 and other zones), if you have your character kissing in zone 2 or 3, you’ll likely have to change your zoom coordinates to suit the zone.
You can choose to have two different zoom points or three and have your zooms quite fast (0.1, 0.2).