Originally Posted by XTheMike
Hello. Is czech language in some of the stock ROMs (probably EU ROM). I know how to flash ROMs but I want to be sure that the language is there. Thank you.
You pretty much have four options. Easiest first, hardest last:
1. Use Morelocale2 to set Czech locale. All apps will speak Czech, only system remains English. That should be enough even for a person that only knows how to say "hello" in English. No root needed and future updates will work.
2. There is a mod by @S0bes
for stock 4.4.2 rom that adds more laguages, Czech included. You will need custom recovery, it only works for 4.4.2 and you will need to reflash stock every time you want to update the ROM.
3. Flash Cyanogen or any other custom ROM. All the positives and negatives of custom ROMs apply here.
4. Flash GPE. Likely the most hardcore of all four options.
If you need any help, you can send me a PM in Czech.
Forgot to answer your quetion
No, Czech is not in any of the stock roms, not even in the EU.