Thank you!!! It mentions very little. Directory - dir - Incus documentation
Unfortunately it will be a huge hassle apparently. I have to shut down server and physically boot initramfs or live usb or something 
# tune2fs -O project -Q prjquota /dev/nvme0n1
tune2fs 1.46.5 (30-Dec-2021)
The quota feature may only be changed when the filesystem is unmounted.
No way around it How do I set up the project quota needed for limiting container storage size for the dir backend on Ubuntu 18.04? - #7 by stgraber