Albert Barnes Commentary Zechariah 2:3

"And, behold, the angel that talked with me went forth, and another angel went out to meet him," — Zechariah 2:3 (ASV)

The angel that talked with me went forth—probably to receive the explanation that was given to him for Zechariah; and another angel, a higher angel, since he gives him a commission, went forth to meet him, being (it seems probable) instructed by the Angel of the Lord, who established the future dimensions of the city.

The indefiniteness of the description "another angel" implies that this angel was neither the Angel of the Lord, nor Michael (if they were different), nor the man with the measuring line. Rather, it suggests an angel of intermediate rank: one instructed by a higher one, and in turn instructing the lower angel, who then immediately instructed Zechariah.