Have the CIA turn enough insiders that one of them succeeds in assassinating Putin after a propaganda campaign raising up an opposition party ready to take over in an election/coup (mixture of both really). Have a weak and friendly leader installed that exchanges nukes for population support and possibly brakes up Russia into several smaller states.
When the USSR broke up, Ukraine gave up its nukes in exchange for security guarantees (lot of good that has done them)
Ukraine gave up more than nukes, it forfeited future membership in russian federation and nato. All the ridiculous bush-era bluster about nato membership for ukraine was in itself a (minor) violation of budapest memo.
Reasonable observers don't think ukraine could have kept russia's nukes, firstly because they were russia's and not ukraine's, and secondly because a country with less than $100B economy (in shambles at the end of the ussr) can't afford to maintain nuclear surety. Additionally, it's very unclear whether any nukes would have been employed by now. Any nuclear attack on russia would result in total annihilation, and if ukraine could only strike a few high-value targets in exchange, it's not a winning weapon or even a deterrent.
Finally the rest of the thesis above is likely to result in a wave of assassinations and sabotage across europe and a wider war that almost all parties have sought to avoid. It's a fever dream shared by angry dummies who are completely incapable of rational thought.
You act like this is a stroll in the park. I would be willing to bet that this is essentially impossible