Ah Ok. Then I understood you wrong, I thought you were asking how to disable a key so that it is not offered in Kleopatra and GpgOL.
Regarding “disabled” keys, that might indeed not be properly handled throughout (I’ve never tested it) as it is fairly uncommon to disable keys in this way and more of an artifact in the OpenPGP Standard. That is why Kleo also does not offer GUI to disable a key in this way. But of course the handling of such keys should be better. They should not be offered and in Kleopatra marked in some way directly visible in the keylist.
I’ve opened a task for this so that it is not forgotten. https://dev.gnupg.org/T4269