Accept Sqlclient requests

Hello, been searching and not finding anything. Is there some kind of way to accept Sqlclient requests, reading them and passing to an actual SQL server? Use case: there's a system from which we have to synchornize some of the requests between two different DBs. Currently system makes direct calls to sql server. Idea is instead of modifying system to call a new API which would synchronize requests, we make a new API which listens for SQL connections. And then read the, if it recognizes that it's specific request. It syncs it between two DBs. If it sees that it's not that request, then it simply passes it to SQL server. This would allow not to modify our existing service one bit, just in connection string point it to different IP:port Hope diagram also makes it clearer