NOW,
Ordasoft
joomla gallery you may show on site with help:
1. Create Menu Item to Gallery
2. Add "gallery short code" to:
- Joomla HTML module,
- Joomla Aticle
- 3rd party components: VirtueMart, K2,
Website Builder...
If you add gallery to site with help menu, You may set meta tags in menu item settings. Please check attachment image
If you add gallery to site with help "3rd party components": Meta tags - you configure in that component
But when you open some exactly Image, we add Meta to web page OG micro data, Google see it and use as Meta data for images. Please check attachment image
Regards
OrdaSoft team