.gen.cpp keeps adding a '&' to a function parameter

try this in the header

	UFUNCTION(BlueprintCallable, BlueprintNativeEvent, Category = "Combat Hex Grid")
	void CreateGrid(UDataTable* DataTable, UPARAM(ref) const TArray<ABasePartyCharacter*> &CharacterList);

const is optional but it’s more optimized if the compiler knows that characters won’t be changed in the function

in cpp

void ACombatHexGrid::CreateGrid_Implementation(UDataTable* DataTable, UPARAM(ref) const TArray<ABasePartyCharacter*> &CharacterList)
{
}

That way you get this in bp

And the override