Why does Wyll have proficiency with swords? Warlocks don't inherently get that. Did the game just fudge some rules and give the origin character an extra proficiency, or what? His patron is Fiend not Hexblade (not implemented, but unlikely given that we've all see the art of his Fiend patron). He couldn't technically get pact of the blade until level 3 (even though the only boon currently implemented in game is pact of the chain). What up?

'Blade of Frontiers'.

Its part of his 'deal with the demon' story line.

Rangers don’t get to use berserker rage, but Minsc could. Same thing here. It’s a deviation from the rules to accommodate a character’s backstory.

Probably just companion flare, or its gifted to him by his succubus person, but yes if you try to build human wyll you cannot use rapier.

yeah, im okay with that, if it make sense with the backstory is okay, havent you talked with a DM about the PC you wanted to make that was a little bit out of the game rules? the same to me

I believe that Wyll made a deal with his succubus to be a hero, so he got given full martial training and rapier proficiency along with a fake persona and reputation. The full story of this isn't in the EA, but it will be added at a later point.

Presumably he will have Pact of the Blade and/or actually be a Hexblade warlock. The later includes:

He won’t be a Hexblade. His patron is depicted right in the banner of this site. That’s a succubus, not a sword.

A Pact of the Blade makes the most sense given his history and has a weapon proficiency as opposed to custom warlocks who only get a weapon proficiency with the magic weapon they conjure from their pact.