YOU SAID:
hey my favorite bestie
INTO JAPANESE
ねえ、私のお気に入りの親友
BACK INTO ENGLISH
hey my favorite best friend
INTO JAPANESE
やあ、私の大好きな親友
BACK INTO ENGLISH
hi my dear best friend
INTO JAPANESE
こんにちは、親愛なる親友
BACK INTO ENGLISH
hello dear friend
INTO JAPANESE
こんにちは親愛なる友人
BACK INTO ENGLISH
hello dear friend
That didn't even make that much sense in English.