This is a very literal translation:
who-to I-speak-ing ?
A more direct (and therefore arguably more Klingon) way to ask would be to say
yIngu''egh! = "Identify yourself!"
or
SoH 'Iv? = "Who are you?"
or possibly
ponglIj nuq? = "What is your name?"
Please go to #1454088.
This sentence has been deleted because it was a duplicate.