Still working in 2023?

Hello!

I still need a solution for my project. I bought some themes from Envato. Each for a specific usage (one is a multivendor marketplace, the other is a community theme using buddypress, another is a learning platform – Masterstudy theme, etc). In total there are 7 sub-sites that I want to build.
My problem is that I want all the users to register in one place (on one sub-site), and after they login, I want them to be users of all of the websites within the network, without them having to login again.
I tried to find you, Pablo Ariel Di Loreto on Slack and everywhere but no results.
From the product’s description this seemed to be a great solution for my use case, but I see that the product wasn’t maintained in the last 2+ years and it’s not compatible with the latest wordpress version.
If there is somebody out there that uses this product, and have a few minutes to have a short chat on whatever platform, please give me a sign.
Thank you!