Hi João. There have been several similar threads on the question of uploading photos of collections made by other people. You may find some useful suggestions in these:
https://forum.inaturalist.org/t/identifying-a-vintage-collection-of-insects/20529
https://forum.inaturalist.org/t/is-it-allowed-to-post-gastropods-observed-by-someone-else/12917
https://forum.inaturalist.org/t/museum-specimens-antique-photos-and-inaturalist/31638
https://forum.inaturalist.org/t/does-a-historic-species-list-have-reference-value/9649
Somewhere in the forum I think there was a discussion about whether if you’re adding photos of organisms collected by someone else it might be better to use a dedicated account rather than your own (can’t remember the consensus on that). Anyhow, it seems to me that these photos would be useful. However, the primary purpose of iNat is to support people in making their own observations in the wild.