Good question, you may adopt a different design and run the decking away from the parallel instead of with it. This way it appears level against the house/wall but isn’t.
By having a run off across the boards may seem a sensible idea and in some cases its acceptable, and some not.
If the boards have a flat surface and they are your normal timber then they may cup which will cause the retention of water… in the cases of Lignia, Accoya and Kebony which shouldn’t pose an issue as these materials don’t cup.
I can’t comment for all composites but I know the Enhanced Grain boards from Millboard are slightly curved on the surface across the board so this is a great solution. There are many composites the don’t recommend this in their installation Manual…