The built-in selling setup connects a workspace to its selling account. The apps using that setup share the workspace's merchant identity; inviting a teammate does not assign that teammate a percentage of sales.
If you and a business partner want to split revenue, agree how the account receiving payouts will account for and distribute the share. Do not assume that adding a role, collaborator or second bank detail creates an automatic per-sale split in the app.
For a client-owned business, confirm whose workspace and selling account will receive the sales before taking payments. Copying the app into a client's workspace also requires reviewing the copy's payment setup and credentials.
If you need automatic split payouts, verify the payment provider's supported setup for your business with support before promising it to partners. Your app's code or a displayed percentage is not proof that the provider will split the money.