I know this is unlikely to be implemented but hey, doesn't hurt to try.

Was browsing through my inventory and realized I have zero DE acc banners, which was ... quite surprising to find. Would be great if there were an option to sacrifce X number of items of the same rank and type to re-roll for another one, along with a similar system to the Forge with charms.

Basically, something like - for each level of the rank, you need one more of that rank. IE for a 6* item to be rerolled, you need 6 items of the same type. So, for a 6* banner you'd need 6 other banners. Then, you'd have substat charms you could apply to boost the likelihood of getting a specific substat, and rarity charms you could apply to boost the likelihood of getting a rarer drop.