Config:
1. You set up an account on the marketplace - sign up, then connect it to Stripe through the marketplace and decide which software you want to sell (about 15 minutes in total)
2. Copy-paste a new license to your repositories - You relicense your software to use a slightly modified version of MIT license, which requires commercial entities to pay for your software (5 minutes or so)
That's all for config, now your part is done and the rest of work is on buyer's and marketplace's side.
You of course remain owner of your software, you don't move any rights to marketplace or users, except the license for usage, just like you do it now with MIT/GPL/whatever license you use right now. Marketplace is only to connect you with buyers and give you centralized place to sell with automated infrastructure, so you don't process payments, signups, etc. by yourself
Selling:
If a company wants to use your software, they need to pay a monthly/yearly fee - you choose how much you charge
License:
You can customize the license if you want - you can choose whether you allow free usage for non-commercial/scientific/charity purposes and you can also set some other feature flags, so you have a control over how your software is used
And that's basically it
There's an MVP on https://poss.market if you would like to check if that even makes sense to you. Thanks and please let me know what do you think if you made it to this point. I still figure this out and your feedback is invaluable to me!