The young Magpies trailed at half-time in their opening Group C clash following Andrew Oluwabori's fortunate finish before Emerson levelled the cup contest before the hour mark at The Shay, netting his first competitive goal at under-21 level in the process.
Ben Parkinson's close-range rebound, after his initial header from Leo Shahar's corner struck the crossbar, sent the visitors in front before Halifax were reduced to ten men in the closing stages following Festus Arthur's red card.
Emerson, a representative of Scotland at under-19 level, told newcastleunited.com: "It was a good game and a proper game of football. It was a strong test but we showed character to come from behind and to a goal we didn't really deserve to concede but we reacted in the right way.
"In the first-half, we had good control of the game but we didn't use the ball as well as we could have and taken as many risks as we should have so, in the second-half, we used it in a more effective way, passing forward and I think that showed.
"It's the tests we need, especially at this age group with players looking for loans. These are the type of games you need to show your character as well as your ability."
Emerson signed his first professional contract with Newcastle United last summer before making his first-team debut for Eddie Howe's side during a pre-season friendly win against Hull City in July 2024.
The teenage winger, who made his under-21s bow at the age of 16 in December 2021, expressed his delight in notching his first goal for United's second-string and is keen to add more goal involvements to his tally during the 2024/25 season.
The Carlisle-born youngster, who joined Newcastle's Academy in 2019, added: "It's good to get off the mark. I think I play well but I need to get the numbers as that's what will get you in the team.
"I want to provide with goals and assists and be one of those players up there in terms of being top goalscorer and I'm going to try and do more of that moving forward."