The formula you mentioned is regarding RPG Maker games. Unity games can be hacked as all games can be. The only difference between Unity and other games is that for Unity games you can access the source code and directly jump to the target function.
Open .NET reflector (I recommend DnSpy it's free) and load all DLL files from the 'Managed' folder. Then either browse the source code manually or search for common things like 'Player' or 'Health'.
You see a health variable inside a PlayerHealth class. Now cancel the search and jump to this class because at first we are only interested in methods/functions.
There is a function called 'Hit' which obviously is called when your player got hit and subtracts the damage from your health. This might be a target location to inject a script that sets your health to super high.
To jump to that location we need the namespace, class and method name.
Which is: Com.LuisPedroFonseca.ProCamera2D.TopDownShooter:PlayerHealth:Hit
Notice that I separate them with a ':'. Copy that and paste it into the memory viewer to jump to this location. Then create an injection script. Unlike CheatEngine CoSMOS supports nested classes as well.
Also on Unity games the structures are automaticially revealed