Tiens, petite question, imaginons que je change les metas en dehors de PM6+, y a t'il moyen de réimporter les metas dans le catalogue (sans refaire les proxy) ?
Use Catalog Sync in Full Mode. It should update the catalog to reflect the changes you made to the metadata outside of Photo Mechanic Plus.
And if images are added in the folder, I imagine that it is enough to remain in quick mode?
Correct. "Quick mode only scans specified folders for new files and adds them to your catalogs."
https://docs.camerabits.com/support/solutions/articles/48001161171-catalog-sync-Kirk