ELM is mostly background coding, and it doesn't change your language configuration, and both version should work regardless; though Omake has new quests/lines/items/NPCS which become garbled if you haven't set your region correctly.
I'm guessing you can't read Moonspeak, so I'll give you the link to ELM.
Direct Download Link for ELMA couple of features of ELM:
Combo bonuses: Each hit builds up a combo meter, which gives bonuses so long as you can keep landing hits within a time limit; it recovers as you land more hits.
Spells have multipliers, which boost effects but use more MP/Stock. (Max is 5x, depends on spell level and casting level.)
You can see your Faith and Stamina levels.
You can choose what recipe to make when cooking.
Statistics that used to be shown as "#" are shown as numbers, like attribute/spell/skill potential, resistances, and equipment effects.
Corpses occasionally drop drugged with love potions.
The game will show when a shopkeeper's inventory is refreshed.
You no longer lose karma when an NPC steps into a fire/puddle you made.
Usable items can have modifiers (+3 Max)
Monster can drop their Egg/Milk/Shit on death. (Written literally as "Lactation, Pregnant, and Scat Fetishes Rejoice!")
Investing in shops increases the quality of their goods as well as their quantity.
NPCs are affected by the Environment affect of the Tower of Flames.
More messages for crits and kills.
Timed Quests show your remaining time.
You can change your pet's AI somewhat (Distance to target, moving probability, and change to use special ammo.)
Shows the amount of damage you deal.
Disables house rank limits (All homes except the Castle have rank caps.)
Change whether training cost depends on your level or your skill level.
Change whether the story dungeon regenerates after you beat it.
Gives you skill bonuses when you level up, this depends on your class.
You can drop a corpse of yourself when you die.
Season changes.
NPC adventurers now have much lower turnover rates.
Imouto Koe Daisakusen! (Mou Ichidou Onegai!)
"The Expressions of Love with My Wonderful Wife" (Your guess is as good as mine.)
A few among many other changes.
Some of these settings can be changed in the Extra setting menus.