Definitely possible, sharing since seems are a lot of unresolved posts.
The main thing is when creating an action on Zapier, don’t select Webflow and then API Request, instead do “Webhooks by Zapier”, because the former doesn’t work and just gives 403 errors. This is probably a bug with the integration.
To create the proper request on Zapier, get the fields from
docs.developers.webflow.com/data/reference/invite-user, and try it out with curl on the webflow page. Log in and it will display the correct authorization key that you can then copy into your Zapier webhook request.
Hope that helps!