Hsv1 stays hsv1 regardless of it's location. If someone who has hsv1 orally performs oral sex on you and transmits it to your genital area, it's hsv1 genitally. Hsv1 will never turn into hsv2.
Both partners should know their status, not just assume that a partner who can't recall a history of cold sores, is negative.
grace
The answer is yes it is possible. If the person has a cold sore or maybe asymptomatic shedding the virus.