Arcanist can't battle ress at level 20, neither can conjurer. Off the top off my head Scholars raise is at 24(?) with the battle ress trait included into it, while conjurer gets a raise much earlier but doesn't get the battle ress trait until level 28.

If you are being synced to level 20, that's why you can't ress.

Also; no point using scholar crystal at level 20, so you'll have 4 skills, as they unlock every 5 levels for classes and 10 for jobs.