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 same way it does now - everyone doing their small part in service of a greater goal. At present, people are motivated by money - someone has money and will give you some if you do some small part in service of their greater goal. Imagine if, instead of that, people did things in service of a greater goal that benefits everyone, and in return, instead of money, they receive a share of that greater goal back to them - in the form of all of their needs being met.
People can organise very effectively and dynamically to achieve goals without coercion. For example, the entirely of the open source movement. Some of the largest, most complex software projects in the world are designed by consensus.