Would I prevent more exploiters if my game was written in foreign language?

It might delay exploits by a few minutes or hours, but that's not really a success. Games with completely randomized, gibberish names are still exploited. Throwing another language into Google Translate does not take much effort, so you won't really discourage anyone.

As much as possible, you should design your game with an adversarial mindset -- assume that every player is a cheater, and that they have full control over everything visible to them (all RemoteFunctions and RemoteEvents, full visibility into the structure of everything, etc). That means you should design your game in such a way that cheating does not benefit you.

The simplest example of this is the follow:

Bad Design: Two RemoteFunctions:

• AwardSword -- give the player a sword
• SpendMoney -- check that they have the right amount of money, and if so, decrease it

Better Design: One RemoteFunction:

• BuySword -- check that they have the right amount of money, and if so, decrease it and give the player a sword

In an adversarial mindset, you assume the attacker is clever (probably cleverer than you!). Something like gibberish names doesn't make cheating impossible, it just means they have to poke at the game more to figure out how it works. And, as mentioned at the outset, because tools like Google Translate are so easy to use, something as simple as another human language will not be effective obfuscation at all.

Exploiting or "Hacking" can be done in different ways. to save you time im going to give you four examples that I learned about. there are of course more ways to hack.

1:Exploitation with Filtering Enabled. filtering enabled blocks changes that the client makes. but there are things that the server will not ignore by default. this includes the players position. and may or may not include things like Player health and tools. if a player spawns a part and then jumps on top of it. the server wont show the new part because it doesn't exist to the server, but because the players position isnt ignored the player will then appear to float in the air. exploiters can use these things to their advantage.

2:code injections I dont know too much about this method but it involves the "hacker" inserting code into your game.

3:autoclicking programs. there are programs that allow the player to click hundreds of times a second which can be a problem because it messes up code that relies on player mouse input.

4: being able to see objects,scripts,etc I once saw a video of an exploiter kind enough to share how he can make changes to a game and essentially "hack" it. this included an external program and being able to see everything in the game(except places like serverscriptservice). I cant provide the link to the video because I dont know were it went but this method is a possibility.

with this all in mind, will changing the language prevent exploitation? probably not, if I were a hacker and everything I saw was a different language there are plenty of things on the internet(google translate) that I can use to understand/translate it. I know this answer is long but I hope it helps you understand how exploitation/hacking works.