This would depend on the abilities in question. All supernatural abilities are sealed on entry to Death City, whether they are genetic or magical in nature. For all other types of abilities the character in question might have, they are approved/denied on a case-by-case system.

However, if you decide for your character to be a Weapon, then you can incorporate up to 4 of your character's abilities as their Weapon ability. If you decide for them to be a Meister, you can take a look at the Meister ability page for an appropriate ability, or suggest one to the Mods.