>>534937754
Saver/Savior in that list is from the first Extra game.
Faker got boiled into Pretender I think, since the 2nd Pretender in FGO calls herself Faker.
Most of that list actually did debut outside FGO.

Alter Ego and Moon Cancer are from Extra CCC.
Also technically for the joke they went with, Karna's official class in CCC is "Launcher" due to just general firepower even if he's a Lancer
(No cringe, Karna's very likeable, chill dude, helps a fat girl a lot)
I know Jeannu was a Ruler prior to FGO and the debut for that class I think
Avenger is actually from FSN as a name, and a character for it from FHA
Beast technically debuted back in Tsukihime because Nasuverse lore gets real silly sometimes

I think Shielder and Foreigner are the only ones to debut in FGO itself.
Foreigner in this case being space and/or eldritch god kind of associations, not just picrel.
And Shielder is unique to Gallahad, and Mash by having his NP, for the gameplay purpose of providing a starting player with a generic unit who could reasonable tank any enemy class by having no weaknesses (no strengths either).