To share a selected album you can create a shared album. People without an Apple device can view the shared album in a web browser, if you enable it as a public website.
To share the photos from your smart album:
- Go to "Shared albums" in the sidebar of Photos, then click "+" to the right of Shared Albums
- Name the album, then add the email addresses of people to invite
- Now drag the photos from your smart album into the shared album.
- You do not have to subscribe to paid cloud storage to use Shared albums. The storage is free. But the items in the shared albums will be reduced in size, so the photos will not be larger than 2048 pixels at the longest edge, and many metadata will be stripped.
For details see: How to use Shared Albums in Photos on your iPhone, iPad, and Mac - Apple Support
If you already have upgraded to macOS 13 Ventura and all people you want to share your photos with are also using Ventura, or iOS16 or iPadOS 16, you can set up a Shared iCloud Photos Library instead. How to use iCloud Shared Photo Library - Apple SupportOfficial Apple Support › en-us
The advantage of the shared iCloud Photos Library would be, that the items will be shared at the full resolution, with all metadata, like titles, keywords, dates, and the subscribers a work with the shared photos and the adjustments will sync back to your library and the items will be shared in the full resolution. But only the photos will be shared, not the albums or smart albums. The subscribers would have to recreate the (smart) albums. And the cloud storage for the shared iCloud Photos Library is not free.
I am adding keywords for each smart album, for example Antarctica_1999. That makes it easy to recreate the smart album for the subscribers of the shared library. They just have to enter the keyword in the search field on the iPhone or iPad, or as a rule in a smart album on a Mac.