Conocerte vs Conocerlo
Encantado a conocerte. = Pleased to meet you.
On the other hand,
Encantado a conocerlo. = Pleased to meet it.
The 1st expression is frequently used and is a correct response to an introduction.
I think you have to wonder when, if ever, "conocerlo" would be appropriate.
I suggest that "conocerlo" is an incorrect response.