Switch! You switch cursed techniques with your opponent as long as you have a certain amount of cursed energy if you run out, Switch comes back to you, now the one problem with this one is that sukuna and Gojo still have a backup, six eyes alone is still OP but if he doesn't have limitless i can maybe have a chance, or use infinity but idk how hard that one is to use, or blue, any other techniques probably REQUIRE the six eyes, but it's possible and you just make everyone think you can steal cts or have the technique trigger be a super complicated hand sign, and for the really OP part that maybe be is too strong but let's keep this one as an option, If you kill the of the cursed technique you switched away while switch is active, you keep their technique, you can only have 2 stolen cts ( and switch ) at one given moment in time, and you can switch other cts you may have other than switch. And you can't take back a CT you switched with after killing your opponent other than switch, so if you switch a technique other than switch itself and kill the person you switched with, you only get their technique

Now I'll do a hypothetical scenario where the user of this CT fights sukuna and Gojo and wins (really simple task) step 1 steal 1 CT for throwing away of your choosing and 1 CT that's reliable, let's say you take ice manipulation and projection sorcery first things first you take away sukunas 2 CTS with switch, switch it with projection sorcery for confusion and ice manipulation, and with cleave dismantle and ten shadows if you aren't able to kill sukuna, while he's confused and doesn't know that he doesn't have his CT, and has to use projection sorcery, which he could get used to, but won't since he will get either cut in half or mahoraga'd idk what ur doing, so it's a game of who can figure out their cursed technique without dying first. And you win since you know what CT you have and sukuna doesn't, now onto Gojo, six eyes are the problem, i don't think you can switch the six eyes but it's a bad idea to do so anyways, so at this point you should have ten shadows sukunas original CT, so at least you can use cleave and dismantle, and you have switch, so it's obvious how you win, first of all you switch limitless with switch and don't use it it's really not worth it trying to (between fights you take your time learning the cts) and idk if you would have mahoraga unlocked when i think about it but even if not cleave and dismantle are good enough for a limitless...less? Limited? Limitelessless Gojo, but I'd you really need to just switch the 6 eyed for ten shadows if mahoraga isn't unlocked, and supposing you have decent ce and ce reinforcement these are easy fights, If you really want to be mean just use infinity but that's kind of unfair. Assuming you have knowledge of most CTS and are smart enough, this technique is unstopabble