Curious, because I haven't kept up with everything lately - where else did this trope happen? I'm assuming Ahsoka, since I didn't watch that show. But I'm curious where else because it seems very new to me, especially in an era where the Jedi Order still exists.
This has been a prominent fixture of SW movies and TV shows, both live action and animated. Persons that have left the jedi order (whether padawan or master).
Anakin Skywalker in Episodes 1-6, the Clone Wars, Kenobi, etc.
Count Dooku in Episodes 2 and 3.
Syfo-Dias (spelling?) is prominently mentioned in Episode 2.
The lost 20 jedi masters are represented in the library scene with Obi-Wan Kenobi and Master Nu in Episode 2.
There is the Grand Inquisitor in Rebels series and (I think?) the Ahsoka series. I cannot recall all the sisters and brothers.
Barriss Offee in the Clone Wars series.
Quinlon Voss who was in the Clone Wars series and specifically mentioned in the Kenobi series.
Asajj Ventress who was in the Clone Wars Series and tested Omega in the Bad Batch series.
Reva in the Kenobi series.
Ben Solo in Episodes 7-9.
Sabine Wren the Rebels series and Ahsoka series.
Ezra Bridger in the Rebels series and Ahsoka series.
I don't even pretend to know all the books to speak intelligently on all of those characters, like Revan or Eeth Koth (who appeared in the movies on the Jedi Council?).
Oh, and I guess Luke Skywalker, in Episodes 7-9.