I was able to find a backup file from two days ago on the USB SSD with an old Rpi3.
Almost everthing is working but I believe it is only a partial backup.
All the HACS addons are installed and working but none of the official addons are installed.
Zigbee2MQTT for example is missing.
Is it possible to find the official addons among the files and copy them to the new NUC?
Probably not, but you can plug it into a Linux PC and possibly find the backup (*.tar) file. Make a bootable thumbdrive. (I use Ubuntu). Boot the NUC from the thumbdrive and select “try”, not “install”. Then plug in the Raspberry USB and browse the filesystem.
Which NUC are you using? I have an Intel NUC i3 and am very pleased with it. I do a full backup every night to a NAS, but there are options to back up to Google Drive.
There are two kinds of Home Assistant users. Those who only occasionally backup, and those who formerly occasionally made backups.
Open the backup .tar file and look for the config folder. Some say that just restoring the config folder works for them, but at the least find the automations.yaml file. If you need to recreate an automation, you can find the YAML for it in the automations file. If you do a lot of ESPHome stuff, try to save the ESPHome folder.