Yes, as long as the external drive is formatted APFS or Mac OS Extended (journaled).
You'll have to import the older library into a new Photos library. With Ventura Photos no longer converts or merges libraries. It can only import them. So if you've put a lot of organizational effort into the library you might want to use the paid version of PowerPhotos to merge the old library into a new one. The following is a comparison of PowerPhotos vs Photos in merging libraries:
PowerPhotos: Photos:
Albums -----------
Smart Albums (as regular albums) -----------
Folders -----------
Captions Captions
Titles Titles
Original images Original images
Edited images Edited images
Locations Locations
Favorites Favorites
Can detect and exclude Duplicates detected after import
duplicates (or not) during import
Neither method included projects.
Both methods could import older iPhoto libraries into a Photos library when the iPhoto library couldn't be migrated into a Photos library.