Stormy Lagoon SMP is a survival world that works on both Java and Bedrock so a lot of different players can join.
The server feels like a simple crossplay SMP where people can just log in and play together and explore and build.
There is also a discord where the community hangs out and talks.
If you want a basic SMP that lets Java and Bedrock play together Stormy Lagoon SMP is made for that.
