This block is similar to the core gallery but dynamically retrieves data from custom meta.
Currently, it has the next supported formats for fields.
Array of URLs
Example of field storage
Array of attachment ids
Array of image objects (ACF gallery type)
[ 1 => [imagearray], 2 => [imagearray2] ]
This type will get all images which are attached to post
Also, you can enable Lighbox and Slider type for images.
Gallery Block supports many design variants, you can set custom output template for each image. Also, you can assign inline videos and Youtube, Vimeo, 3d (gltf and glb, splinecode). Check design examples and instructions in description of Gallery Block