I would consider a solution like Tipalti (https://tipalti.com/), depending on the scale of the problem.
It will handle the onboarding of payees and also the disbursement of payments globally along a variety of payment rails. It has an open API.
Probably the best solution if the economics make sense.
Edit: for context, this is the tech that Twitch, Roblox, etc. use to pay their users. For this purpose it is easily the best solution on the market.
Disclaimer: I work at Tipalti.