Hi sergiodj,
Welcome to Incus!
What I do is export directly to a mounted backup server (I’m using NFS) instead of the “incus export” native operation of backup and then move. This cuts the backup dramatically because the creation of the export is the bulk of the time spent in “incus export”. See GitHub - AJRepo/incus_tools: Tools for Incus and Cleaning up Incus export orphaned backup file and general backup question - #4 by AJRepo