For now you can just copy the LN address from coinos (looks like an email) and add to your LN address field while editing your profile in amethyst.

nostr:npub12ekpvme6m2cv37a9mgq4kzemej8tx6ttg40j582rh77ewpvkg65qj8tq0f is working on adding NWC/one tap zaps with coinOS. Not ready yet.