If a president discusses with his cabinet how to fight a war in a way that is possibly illegal (and then orders it), that is an official act, executing illegal actions, and is immune.

What is the difference between that and preventing the transfer of power to your political opponent?

Especially since now parts of your activity's are "official" and cannot be mentioned in court, and part of your activities are not official which are potentially prosecutable, see Barrett's arguments.

Got to love it when supreme court creates all these exiting new laws.