The "14" most likely refers to (or a similar iteration) of a specific fan-made ROM hack. Many ROM hackers update their creations over time (e.g., v1.0, v1.2, v1.4). In this context, "14" could mean:
Downloading ROMs of games you do not own is generally considered illegal. pokemon omega ruby 14 rom 0 gba espanol
If you are looking for an experience similar to Omega Ruby on a GBA emulator, there are several fan-made projects: Pokémon Edición Omega : A hack ROM in Spanish based on the original Pokémon Ruby for GBA. It features: Updated graphics and animations. Two playable regions and 386 Pokémon. Modified events and characters. Version v1.4 Updates The "14" most likely refers to (or a