[vimy]

You can just charge subscriptions for local first software. No cloud is irrelevant. Only the value to the user matters.

[danjl]

Where do you check their subscription in order to cut off the service when they stop paying? One of the nice bits about local first is that there's no need for logins. Do you install security software in your local first app, which, typically, includes the code in a format that's fairly easy to bypass? Pirating desktop software was a big issue for companies. Are we going back to that horrible world?

[vimy]

A simple license key and monthly ping to license server (5 usd digital ocean) is enough.

Pirates is the cost of doing business. Just ignore them.

No need to make this too complicated.