A fair question to ask of any asset tool, so here it is plainly.
Collections, assets, generated barcodes and scan history live on the device. There is no SweepTag account and no SweepTag cloud to upload them to.
Data leaves the device only when you send it somewhere yourself: an export to a folder, a NAS over SMB, iCloud Drive, or a print job. Lansweeper is a read-only connection to a server you already run.
If you want a copy elsewhere, Settings › Data exports CSV or JSON, and those files re-import cleanly — so export doubles as backup.