Blackmagic eGPU with 2 5ks on mac mini

The 2018 Space Gray Mac Mini was the only model that could fill both of those requests.

The 2020 M1 only supports one 4K display from the HDMI port and one 6K display from the TB/USB-C port.

For more on that see > https://support.apple.com/guide/mac-mini/connect-a-display-apd8e4fbbb97/mac

Plus the M1 does not support an eGPU.

see > https://support.apple.com/en-us/HT208544

Then you will need to buy an Intel model and/or look for a used or refurbished 2018 Space Gray Mac Mini.

Yeah’ that one.

FWIW I bought refurbished 6-core i5, 500 GB model from Apple last year, and upgraded it to 32 GB with OWC RAM.