RGB Correction with ATEM Mini?

My church has begun using the ATEM mini attached to PC with OBS (for overlays). One of the fixed cameras seems too red (and has no internal adjustments), so I'd like to adjust the RGB for that camera input only. There is RGB adjustments with the downstream key I believe, so is there a creative way I could use a "dummy" key for that camera input exclusively and also attach RGB settings to that key / camera? I'd love to all be automated so the large 1/2/3/4 buttons still just switch between camera views.

Just beginning to learn the ropes, so i appreciate any ideas you might have. We streamed out first service last Sunday with this setup, and it went quite well. I'm using the ATEM usb-c output as a webcam input on OBS, so we can just point a click for preconfigured overlays and media.

The downstream keyer is really for configuring overlays, not color correction. The only color correction features built into the ATEM switchers are the camera control features. This works by sending color adjustment information to the cameras which then change their output, so it only works in conjunction with specific Blackmagic cameras that can respond to the camera control commands.

If you just need a fixed color adjustment for a video input that stays consistent throughout a broadcast or recording session, you could probably use something like a Mini Converter SDI to HDMI 6G and load a color LUT (lookup table) that changes the colors of that video signal. The Mini Converter SDI to HDMI 6G only has an SDI input, so if you are using a camera with an HDMI output, you would also need an HDMI to SDI Micro Converter for this kind of setup.

It's not easy to do live color correction adjustments with this type of approach, since you have to load the color correction LUT file in advance, so it's not easy to change on the fly. But it could work for tweaking the colors of a video input that needs consistent adjustment in a particular way.

There is no way to do this and still use the buttons 1-4. However you can set up a chroma key and use the red input camera as source. Set the key so that the picture are solid and then use the chroma key adjustments to reduce the red in the picture. You have to cut to that camera with the key on and key off buttons.