The world location is set to, 'External' in the game settings and Minecraft has the storage permission granted. Even so, the world folder is empty.

Context: I was trying to export a world from my current device to another as I want to upgrade it. Going into file-manager I couldn't find the 'games' directory at the 'home-root' folder i.e 'storage/emulated/0/'. So, I figured maybe I haven't changed the world location from 'Application' to 'External', still no luck. Then I tried creating a new world at this configuration as I thought maybe old world won't get moved to 'External' anymore. Still no luck, but I saw that there was that 'games' folder has now been populated by 'com.mojang' folder which is populated by several files and folders such as 'behavior' and 'resource' packs etc I was finally glad. But I got my hopes up too soon though, after going inside that folder and checking the 'games/com.mojang/minecraftWorld' folder it was still empty and whatever I did I wasn't able to see my world there.

Also, I tried it on my other device and it's "world" folder was also empty regardless of what I did.

Maybe Mojang should add an export world to '.mcworld' feature to the mobile app.