Should this work for maps aswell?
The short answer is: No.
You can add SFS archives to SFS_AUTO and replace
existing stock objects appearance with the HSFX one, that's why we're talking about eye candy only.
If you want to add maps, you have to add and edit the regarding ini files as well.
And once you did so, you will notice that the maps have objects on them which are missing from Stock IL-2.
So you would have to add these objects, like buildings, runways, ships, tanks, cars etc.
When you got there, you'll notice that your missions still won't run because you're again using objects in your missions which are missing in Stock IL-2.
So back to start: Add all the missing objects, including java classes etc.
In the end you'd be asking for HSFX on 4.13.4, something that doesn't exist since 242 Sqn abandoned further HSFX development.
If you want to play HSFX, play HSFX.
If you want to play 4.13.4, play 4.13.4.
Both at the same time is a no-go.
Best regards - Mike