Can't wait if this is true I loved the original Digimon series! I am against Digimon being referred to as an Isekai. It might start out as one but it quickly moves away from Isekai territory. The kids don't stay trapped in the digital world their able to make it home and can freely travel between both worlds!

Mushoku Tensei: Jobless Reincarnation is the only one of these I watched. I agree with Greg Mushoku Tensei is one of the best Isekai anime I've ever seen!

I haven't seen Bofuri: I Don’t Want to Get Hurt, So I’ll Max Out My Defense yet but I'm planning on watching it tonight! If what Zach says about it is true than Bofuri is not a true Isekai anime and should not be on this list!

Isekai is where a character or multiple characters get magically transported to another world usually a magical one in which they have to survive and thrive in this new magical world. Usually this transportation happens because the character or multiple characters have either died in their own worlds, have been pulled through by a magical calamity, have been summoned to fight, or even got trapped within a "magical" game world.

However each one of these scenarios have specific "rules" that are typically followed throughout the entire anime, manga, etc.

For the last one, where the character or multiple characters get trapped within a "magical" game world, there's one big "rule"...

The character or multiple characters can not just hop in and out of the "magical" game world they are trapped in at will without rhyme or reason. The trapped characters are usually friends from outside or quickly become friends once inside the "magical" game world. The rhyme and reason bit, sorry there's probably a better way of phrasing that, is the tricky part. If an Isekai accurs with one main character then all other subsequent Isekai'd characters have a looser leash so to speak.

A good example of this is .hack//Sign. I watched enough of it to know it's about a kid who gets isekai'd into a "magical" game world. This one kid is trapped within this "magical" game world either by their own choice or some other reason, I can't . All other characters are either isekai'd before or after this kid was. These characters can come and go from the game at will, I believe though I might be wrong...