i think chikako is earth child but don't go naming your kid that until you verify it
Some Japanese girl names that mean lonely are Sabishii, Kodoku, and Hitori.
Erza =D
Yuuki means brave but I don't know warrior !
By main characters, I think you mean the player characters. If so, yes, they have names. The boy is named Hilbert, and the girl is named Hilda. Their Japanese names are similar as well. The boy's is Touya, and the girl's is Touko.
names meanings do not change when translated in Japanese
Names in Japanese are not always meaningful. Whether or not they carry any meaning and if yes what they mean depends on their spelling; names in Japanese can have several spellings so a certain answer is impossible.
names do not translate meanings do
If by English names you mean into romaji - which is a readable version of Japanese then yes there is. An example of what I mean is; 日本国 - Nihonkoku Meaning Japan. http://www.romaji.org/
whats it mean in English names don't translate
The only name for both female and male names that mean death is Shi.
it means bad girl in Japanese...
Yes it is. There are numerous ways to write the name Rika in japanese with different meanings.