WP Core version 6.4 brings the native support of storing the post meta in revision.
There is a filter wp_post_revision_meta_keys
to define what fields should be saved by providing the meta key, but it didn’t work for me with ACF fields.
More on this: https://make.wordpress.org/core/2023/10/24/framework-for-storing-revisions-of-post-meta-in-6-4/
Are you planning to hook into these autosave process improvements? This issue bounces back for ages on this forum and it would be great to finally make it work.