Desktop Mode; Change INSTALL location

As the title says, I am trying to find out how to change the INSTALL location when in DESKTOP MODE.

I have searched and searched and all explain how to change INSTALL location when in GAME MODE, this I already know this.

I already know how to change other directories to the SD CARD such as: DOCUMENTS PHOTOS MUSIC DOWNLOADS

But I can't find anything anywhere on my SteamDeck or online to change the directory in which content will install to when in DESKTOP MODE.

So for example when I use DISCOVER to find an emulator and INSTALL it, it by default installs to my INTERNAL STORAGE.

I don't want to waste time trying to locate the directories which everything installs to.

I would like to know how I can change the INSTALL DIRECTORY to my SD CARD as DEFAULT for EVERYTHING I INSTALL when in DESKTOP MODE.

So, when I INSTALL an EMULATOR as an example, it will INSTALL to my SD CARD.

Thanks.