YOU SAID:
Hello if you are cool
INTO JAPANESE
かっこいいならこんにちは
BACK INTO ENGLISH
Hello if it's cool
INTO JAPANESE
良かったらこんにちは
BACK INTO ENGLISH
Hello if you like
INTO JAPANESE
よかったらこんにちは
BACK INTO ENGLISH
Hello if you like
That didn't even make that much sense in English.