I don't get why they always overthink monetization when they figured it out in the very first game
>hey you can buy some skins if you feel like it no restrictions at all on where you use them
Which incentivizes people to indulge in the occasional microtransaction because they know they'll get to use their cosmetics. COD and Fortnite understand this intimately.

Tying characters to specific classes in the hopes you'll get people to buy more across classes is just going to have the opposite effect.