I'd say the first things I've seen with the concept were probably stuff like Neverending Story, Peter Pan, Alice in Wonderland, and possibly random cartoons long before that.

For Anime, Fushigi Yugi and Escaflowne I both saw before SAO. Maybe Dual! Parallel Trouble too.

I tend to count stuff like .Hack and SAO as VR not isekai myself, as your body doesn't really get stronger in the real world, and usually your life in the real world isn't as affected either. For the ones who have that pining for a real adventure, I prefer permanent changes to "it was all a dream or might as well have been because their are no material changes."

[–] dudewitbow@lemmy.ml 3 points 11 months ago

Some people forget isekai is pretty old. For late 80s and 90s kids, Digimon and Inuyasha are isekai (well Inuyasha is closer to portal fantasy but isekai on its own is a sub branch of that).

Hell, Spirited away is isekai, and i can bet most people watched that before SAO. SAO just happened to be the most popular isekai at the time that isekai became mainstream and abundant.