Can Excalibur II be acquired on the Android version of FFIX?
According to the Excalibur II Wiki, you can get the weapon on the mobile version the same way as you would on the other platforms while also being easier to obtain.
Challenge
....
The Steam and mobile release makes the challenge substantially easier as cutscenes can be skipped, random encounters can be disabled, the player can stat boost their players to defeat enemies quicker, the battle intros can be disabled and the player can speed up their game by five times without affecting the internal clock. Even without speeding up the game, it is easily possible to claim the sword in under nine hours by making use of all other enhancements