The semi-done 1.13 version of the ReplayMod is available here: https://github.com/ReplayMod/ReplayMod/tree/johni/1.13-pre
It won't help you though because an integral library (SpongePowered's "Mixin") which we require for anything notable to function has yet to be updated to 1.13. That means you cannot run the mod in production, you can only work on it in a development environment and only using quite a bit of workarounds can you run it there (which is how I've been updating it to 1.13 already even with that lib still missing).