(If anyone here would like to correct me, please)
This is similar to what you want to make a multisite inside a multi-user. Multisite probably didn't work like that.
When you create WordPress Multisite, you are prompted to customize it using a subdomain or subfolder structure. You can switch, but you cannot mix it.
A possible solution would be to make a subdomain in your hosting package (s.example.com) and configure a separate multisite (with a subfolder structure) for this. The downside is that you will have 2 separate networks instead of 1 network.
Similarly, you can: s.example.com/site-1, s.example.com/site-2, www.example.com/site-1 and www.example.com/site-2
Ravi lautan
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