I've written many strategies on MT4 and MT5.
I wrote for a client here on freelancer (but it was paid externally , so i didn't receive any points), a full blown MT4 and MT5 trade system, that read from a web hosted file the signals...All (and there were many) MT4/MT5 terminals read from that file, and passed the trades (with various checks , as you can imagine, if there is already an open trade, the time checks , setting up the limits and stops).
It's somewhat different than your system, but at the same time similar.
I'm definitely the guy you want to write your strategy.
Best.