Can you help me with a question? I have 11 Mikrotik servers. All my users are inside the first Mikrotik server. In the first Mikrotik Wireguard, there are about 10 IP ranges, each directed to a separate server. The problem I have now is that I have to pay for traffic both for the first server and for other servers. Is it possible to point the first server only to other servers so that the first server does not give me traffic? Note that all servers have public IPs and are from different datacenters, and my users are connected to the first Mikrotik server by Wireguard.

Sorry but your question is a mess. Assuming that "server" means router.

How do you expect that the first router could not generate any traffic if WG users connect to it?

Push them to connect to other routers but then what you need this first router for?