Preliminary work has been done.
Here is how to unlock the device:
https://xdaforums.com/t/all-in-one-xiaomi-14-houji-unlock-bootloader-root-flash-twrp-flash-rom.4659853/page-3
At some point, a lineageos beta was worked on, but it disappeared early 2025:
https://xdaforums.com/t/closed-a14-beta-lineage-os-for-xiaomi-14-houji.4691530/
There is also this other alternative here: