The current pre-release of the client ("pioneer" in the version) is only compatible to itself. So you can only play with other testers. Please be aware!
Best place to make a sudjestion like this would be over on the faf client GitHub repository. https://github.com/FAForever/downlords-faf-client/issues/new/choose here you can create a feature request and the maintainers are more likely to see it.
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