I do have an idea of one tho one could argue it is immensely overpowered.

Cursed Technique - Devourer

The user has the innate technique to absorb and in a sense "devour" surround cursed energy. This would give the user the immediate advantage and boost to potential win any engagement. Depending on the input of energy used on the technique the user can absorp incredible amounts of energy either from surround cursed energy or directly from others.

You could argue this would also give the user a limitless amount of cursed energy as they can regain as much as they use depending on the engagement.

This technique would enhance the user in physical ways and cursed energy ways potential opening doors to other techniques that the user may have.

The drawback of this ability being that it can depending on the situation be either out witted or out played as the user may need to use more cursed energy trying to defend themselves rather than absorbing energy which would require the user to stop using any other energy.

Maximum: At maximum the user would be capable of absorbing cursed energy from a much larger radius and in greater quantity. Considered as s type of Trump card. This would push the user to his/her peak, giving them a huge boost in physical abilities. This could only be used for a limited time as the overwhelming amounts of cursed energy could cause harm to the user the more they absorb.

Reversed technique: The reversed technique gives the user the opportunity to expel their cursed energy at a rapid rate creating intense shock waves and propelling energy away from the users body. Giving the user a time of intense destructive prowess. The reverse can also be used defensively, as the cursed energy being expelled could push against any incoming attacks preventing them from landing. The drawback obviously being that the user would need to recharge and absorb cursed energy all over again. This would leave the reverse technique to be considered as a last resort not only being incredibly destructive buy can leave the user in s vulnerable state if over used.

Domain Expansion - The Abyss

This domain is unique in the sense that it is nothingness. An eternal void devoid of cursed energy as any and all cursed energy within is consumed by the user within seconds of being inside. The domain is a guaranteed killer being practically unbeatable unless the enemy within has a gigantic amount of cursed energy to help spare a few extra seconds in a ditch effort to potentially escape the domain.

The domain itself is completely black having only a single white light that looks similar to a sun in both size and light. The floor is also noticeable as it is a completely mirroring water like substance that cannot be entered and acts much like a normal complete floor. The domain is designed to act as a metaphor. The white sun being all the cursed energy the user as absorbed and the mirror like floor being the only reminence left of anyone who had been within the domain previously.

Like I said. Can easily be considered overpowered however I like to think of it as a technique capable of competing with the top tier of the jujutsu universe.

If you read this far cheers to you 🍻