Seems like an interesting effort. A developer is building an alternative Java-based backend to Lemmy’s Rust-based one, with the goal of building in a handful of different features. The dev is looking at using this compatibility to migrate their instance over to the new platform, while allowing the community to use their apps of choice.
This looks like the major driver of the project, IMO. The Sublinks roadmap is full of feature ideas geared toward better moderation, both at the community and instance level.