I've tested with FB2K 1.0.94 and 1.1.5 on Android 7.0.
I've tried adding several .7z and .zip files from various sources to both my SD card and my internal storage, and foobar2000 doesn't see any of them, neither in the library or in the file browser. I've verified that it's on my SD card and internal storage by using a separate file browser to check. I also tried enabling "Show non-audio files in folders," and they still don't show up.
Was archive support removed somewhere along the way, or am I doing something wrong?