Plastic Man (1988) #1-4 A slightly more "adult" reboot of the original concept. Very 80s comedy-noir; lots of fun.
Modern
(Note: There are sort of three incompatible branches here, each one of which gives him a kid at some point. Pick any or all.)
Main DC continuity
Heavily involved with many large DC events. Cosmic threats, team world-saving. In which O'Brien tries to reconnect with Luke, his equally flexible biological kid.
Optional continuation in Injustice 2 #16-24, wraps up in #27 (Set in "Injustice" again. Father and son help out fighting ecofascists.)
Kyle Baker continuity
Delightfully off-the-walls indie writing. A parody version of the DC/JLA universe that sticks closer to Jack Cole's continuity. In which Plas adopts Edwina, a goth girl.
More modern crime-noir flavored reboot. Very loosely tied to everything else. In which Eel accidentally becomes ward of a street kid that calls themself Pado Swakatoon.