Trials of Mana

– Cache embedded
– Works offline
– APKS installation via ZArchiver, XAPKS Installer or SAI (Split APKs Installer). Before installing, free up at least 15 GB of memory space on your device.

P.S. the first launch of the game is very long – it is unpacking resources.

How can I reduce the 5 GB of space the game takes up?

You need to enter the game and wait for the main menu to load. Then unzip the apks file you downloaded. And install only base.apk (as an update).