Hey there @x2lovi! Welcome to the community! Sounds like the water plugin failed to generate the collision profile in the DefaultEngine.Ini when it was imported! So we can just pop that back inside there and that should allow the build to run.
So head on over to your project folder, then Config → DefaultEngine.Ini and scroll on down to wherever your collision profiles start roughly around line 200 for my project but it varies. It’ll look a bit like this (I’m using notepad++ for this example but any text editor will do).
[/Script/Engine.CollisionProfile]
Then add this line on it’s own line but under that header, Save, then restart the engine and let me know how it goes!
+Profiles=(Name="WaterBodyCollision",CollisionEnabled=QueryOnly,bCanModify=False,ObjectTypeName="",CustomResponses=((Channel="WorldDynamic",Response=ECR_Overlap),(Channel="Pawn",Response=ECR_Overlap),(Channel="Visibility",Response=ECR_Ignore),(Channel="Camera",Response=ECR_Ignore),(Channel="PhysicsBody",Response=ECR_Overlap),(Channel="Vehicle",Response=ECR_Overlap),(Channel="Destructible",Response=ECR_Overlap)),HelpMessage="Default Water Collision Profile (Created by Water Plugin)")