Import sequences natively produces black video unless disabled

Ran into a series of bad exports when trying to use Frame.io and sending Export nobs from Premiere to Media Encoder. Video was black, despite using presets where "video" was clearly enabled. Audio was normal. Turned out it would happen each time I sent exports to the Media Encoder queue from Premiere. Only disabling the "Import sequences natively" option in the Settings fixed this. 

Both Premiere and ME are v23.6. Using an M1 Ultra Studio with 64GB of RAM, 20 core CPU and 48 core GPU, 2TB internal storage. Exporting to internal drive. Initially used Frame.io and "upload sequence" to send to ME, later just used regular Export to ME command in Export window (same results).