I agree that the match between Roma and Brighton will be difficult to predict as both teams have similar strengths. However I believe that Roma has the edge in terms of experience and recent improvements under De Rossi coaching. Their performance in the Europa League and reaching the final last season shows that they have the ambition and mentality to succeed again this season. I think Roma will have a slight advantage in this match. So let's see.
I don't think difficult to predict the winner between AS Roma vs Brighton Albion, in this season Brighton have dropped perform in Premier League and current standings dropped until 7th place. I don't think Brighton will be favorite time for winning against AS Roma with consistency performance in domestic league after sacking Jose Mourinho and replacing by Daniele De Rossi.
AS Roma have much experienced playing in Europe League than Brighton Albion become their first appearance this season and AS Roma performed last season success lead until final round.
Playing as home match on first leg, I think AS Roma have bigger opportunity for defeating Brighton Albion exactly with their attacking line on top perform with Paulo Dybala and Romelu Lukaku had impressive performance.
The AS Roma club has experience in the European League. But their coach, De Rossi, doesn't have much experience in the European League in his coaching career. So I personally might prefer to think that this match will be quite fierce. Even though I will also favor the home team, I am still not sure whether Roma will be okay in this match. Because I still remember that Roma also had great difficulties when they faced Feyenoord in the knockout round. And Roma was actually able to qualify for the round of 16 because they won on penalties against Feyenoord. So for me the first leg is still a match that is difficult to predict. But I prefer to bet on the home team of course.