Before uninstalling Agisoft Metashape please deactivate the product following the procedure: Help Menu -> Activate product command -> Deactivate button. Deactivation can be also performed from the command line using --deactivate argument:
on Windows:

metashape.exe --deactivate

on Mac OS X (example for PhotoScan Professional): --deactivate

on Linux:

./ --deactivate

Please note, that de-installation of Agisoft Metashape does not deactivate the license automatically. If you have uninstalled the software before deactivating it, please re-install Agisoft Metashape and run deactivation procedure, as described above.

To uninstall Agisoft Metashape on Windows OS open Control Panel -> Programs and Features window, then locate Agisoft Metashape in the list of installed programs, select it and click Uninstall button.