There's no way to sync simulation time across water surface for multiplayer

The idea is to have a function to be able to sync the simulation time once so that multiplayer game using water show the same experience to users at the same time.

Once the simulation are synced, they shouldn't drift with time.

Cf forum thread: https://forum.unity.com/threads/water-system-for-the-high-definition-render-pipeline.1203751/page-7#post-8657838