So if you want to do both paths but don't want to or can't use this mod I can help out.

It's important to remember to turn on the obsolete focus tree branches custom setting or you will have to repeat this process but if it is just a one or two focus tree branch this can work well. (I am trying to find what the line to change the setting about the obsolete focus tree branches are in the save files is, so might update if found)

First you will have to go to setting.txt in C:\Users\User\Documents\Paradox Interactive\Hearts of Iron IV and change "save_as_binary=yes" to "save_as_binary=no" this will allow you to edit new save files. Save changes. (remember to change back later or delete saves regularly this cost me like 300gb of storage since it doesn't really compress the saves)

Go ingame and make a new save.

Now you will have to access "save games" in C:\Users\User\Documents\Paradox Interactive\Hearts of Iron IV and edit the save you just made.

You have to find your focus tree now depending on the nation you will have to search for different IDs of the focus tree with the search function, in my case, for the german focus tree it was: "german_focus", in the base game they all seem to be like this so for france it's "french__focus".

If you see something like this:

focus_tree="german_focus"
continuous_focus_palette="generic_focus"
focus={
progress=1.000
}

You have found the right lines.

in this clause you have to add the following:

focus={
progress=1.000 #This shows the progress of the focus progress might not be
here for you.
completed="<Focus ID>" #To find out the ID complete the focus ingame and
check back here in the new save file or just guess
the name ex: completed="GER_oppose_hitler"

}

The Hashtags are just notes for you.

Now you can write both focuses here but this will just complete the focuses without giving you the effect.

To gain the effect just complete the focuses ingame, without making any changes yet and remove the newly created line.

Then get back ingame and do the other focus.

Come back to the save file and set both focuses as completed.

You should be done now if you have any questions ask them and I will try to reply quickly.

It is a very tedious process so I might make this into a mod, or if the mod developer of this mod sees this he could try to change into a system like this. Though I haven't modded anything in hoi4 yet so no promises.

Hope this helped.