Display mirroring prevents higher resolution than 1920x1080 on 2k monitor

So this might be a me problem (or other dual pc twitch (content) streamers) but I stream on twitch with 2 pc's at 2k resolution 3440x1440.

This isn't a problems for any other games, i know this is beta and i figured this should be feedback instead of criticizing a broken feature.

What i do is i have a display port from my RTX 3080 to my Monitor, then an HDMI out from my RTX 3080 into my Elgato HD60 s, and then i mirror my ultrawide display to the hdmi output so that my 2nd pc receives the exact same thing i see instead of using HDMI passthrough because my monitor utilizes the Display port for the max features of my monitor.

With this configuration, i can only get a max resolution or 1920x1080p and nothing higher and i cannot get the apect ratio for it either.

What i discovered is if i don't mirror the monitors (Monitor 1 mirrored to Monitor 2) and i lets the elgato act as a extended display (not what we want) it launches the game correctly, all the way up to 2k resolution.

I can run any other game perfectly fine at 2k resolutions and if i have a problem and i dont see the resolution, usually setting borderless and editing the config for example, rocket league, i can set the resolution manually and it works fine after that.

I can't seem to find a fix for Battlefield 6, no way to set a custom resolution or a way for me to get a higher resolution than 1920x1080p when i have my display mirrored. This is a must for me personally considering its not a problem with other games.

Any one have any similar behavior or found a fix for this? I'd like to stream it but i can't get play it weirdly stretched on my ultra wide.

<3