The pair caught their manager’s eye in the draw against the Black Cats.
The Hornets had 57% possession in the game but were denied the three points by Jewison Bennette 87th minute equaliser.
Edwards told the official club website:
“Asprilla is a very talented boy. He is someone who can play in the forward line in about four different positions. What was really pleasing today was his work rate and his intensity in and out of possession. That was as impressive as when he was on the ball.
“He’s got a great personality when he’s on the pitch for someone who doesn’t speak the language. He’s still got lots to learn and there are loads of areas he can keep improving, but he’s only 18 and that’s just normal. We’re really excited, and we’re thankful we have got him.”
“I was also really happy with Keinan Davis. He was really positive, and you can see in his all-round game that when the ball comes to him it sticks.
“He can really bring people into the game, and I’m really pleased he got his goal because that is what all strikers want. We need that, because we need players who are in-form and scoring goals.
“He needs to keep working hard, because there is a lot more to come from him.”
Asprilla, 18, is one for the future at Watford and has been in impressive form so far this term.
The promising Colombia international is enjoying plenty of game time under Edwards.
Davis was brought in last month on a loan deal from Aston Villa to add more competition and depth up top.
The striker helped Nottingham Forest gain promotion to the Premier League in the last campaign.
Watford go into the international break sat in 10th place in the league table and are back in action on 2nd October away at Stoke City.