Except a few exceptions like item with blueprints, purple MI’s and items unique to specific totems; all legendary items can be drop in anywhere and it all based rng.
One of the easiest ways to farm legendary items is playing main campaign in ultimate level. You can farm totems; other hero monsters and roguelike dungeons etc; check locations from here https://www.grimtools.com/map/
But you can also have chance to get legendaries on normal/elite. It all depends how efficient your character kill enemies.
You can do Shattered Realm in normal/elite or in ultimate. Shattered Realm Loot Table Check this to calculate best farming range for yourself. I think there was some video from MikeFic aswell but couldn’t find it in forum.
Anyway your character’s damage type and class doesn’t affect the loot or any other rng based function in the game.
You can also post in trade section here FG SC legit trade thread #1 if you know which items you’re going to need and offer some mats in return.