What're the least and most lore-friendly jobs for an RP character to have?

[Cygnia]

As Vyrerus thankfully points out, at some point a tradition was invented (and doubly thankful for once mention of Scholar's job was not prefaced by the disclaimer those fairy soulstones cannot be found outside Nym). There is unfortunately a lot of conflation between method and specific traditions still despite Square writing class/role quests showcasing strangers executing much the same skills as our White Mage/Black Mage etc.
The only restriction I'd bear in mind is acquiring the job exactly in the same manner as the Warrior of Light for some jobs might be a trifle difficult, but otherwise the sky is the limit. Adventurers by their nature tend to stumble across hidden knowledge on the regular.

P.S Illegality never stopped the criminals from multiplying, why would the forbidden nature of White/Black magic be cause for concern? Fairly certain 'twas an entire nation or two regularly using such magic which led to ruin, plus some Ascian meddling.