CC forehand: Nadal
IO FH: Federer
II FH: Nadal
DTL FH: Nadal
Running FH: Nadal
Sliding FH: Thiem
Early FH: Federer
Return FH: Agassi

CC BH: Djokovic
IO BH: Nalbandian
DTL BH: Nalbandian
Running BH: Murray
Sliding BH: Djokovic
Early BH: Djokovic
Return BH: Djokovic https://twitter.com/MardyFish/status/1247931564740112389

Disguised T serve from both sides: Sampras
Kick serve: Isner
Slider: Muller
Flat first serve: Karlovic or Kyrgios

Back tweener: Cuevas
Front tweener: Cuevas
Superman shot: Monfils
Squash FH: Federer
Fake smash drop shot: Cuevas
Slice BH: Federer or Dolgopolov
Tweener lob: Nadal

Drop shot: Nalbandian
Hardcourt movement: Djokovic
Clay movement: Nadal
Grass movement: Federer
Smash: Sampras
Backhand smash: Federer
Sky hook: Nadal
Reverse sky hook: Nadal
Reverse sky hook dropper : Nadal
Volley: Edberg, but I didn't see him so, I dunno, Stepanek?

The sky hook dropper is a joke based on this: https://twitter.com/CalebPereira23/status/1147526716413206528?s=20