This functionality is not built in, but we did add a kind of “sponsorship” feature for a client. It takes a bit of work, here is how we did it:
1. Added a second membership level for the “sponsored users” (your variants)
2. Set that level as hidden so people could not checkout.
3. Added an interface for true users to “invite” a sponsored user to their team. The invited email address would be stored in a table.
4. The invite email would contain a link to the sponsored member checkout page with &[email protected] in the URl.
5. Added code to check for that email parameter in the URL and allow the user to checkout if the email was in that table we created.
6. We also maintained a user meta field with the number of “seats” the true user signed up for. Each invited user would count against that seat. There is a bunch of code to allow people to increase the # of seats (they checkout for the same level at a higher price).
Hope this helps.
