Give editor access to client on only one project

Hi, I want to give access to a client to edit the text in page in the website I’m building for them.
I currently have an agency account and have many sites for many clients in my account.
If I understand correctly, I would need to buy another licence so my client could log in my account and I would then only give them access to their particular site with an editor permission.
But when logged in, they would see my whole account when in Webflow?
I would like to have a licence that would limit the editor to only their website.
Another solution would be to have this client have a Webflow account and I would then move their site to their account, but that seems a lot of work just so they can only see their website in my account.
Can someone tell me how to solve this? Thanks.