Posting to 'grad because I don’t know where that’d belong on 'bear. I hope it’s OK!
I genuinely cannot see how anarchism could work large scale, but there are anarchist spaces: anarchist communes. I think after a leftist revolution the world would be generally communist, but there would be independent anarchist communes. I think that’d be a true way anarchists and communists could coexist in reality. Alongside one another but not forced to abandon their political stances.
The issue is the revolution is not an instant snap to full communism. There will need to be structures in place to prevent the slipping back into capitalism, and the undermining of the new proletarian state by internal and external forces. This means things like police, military, and government, but fundamentally different as the structure of the society they serve will not be designed to protect the wealthy. The transition from revolution to full stateless, classless, moneyless communism will take an unknown amount of time.