Serge is a quality right winger, 99 acceleration makes him lightening quick, you don't need to touch the pace so I went for marksman as a chem style which gets his power, finishing and long shots to 99 which is amazing. With a 4star weak foot this means you can just smash it when anywhere near the box and you have a decent chance of scoring. Only downside on shooting is the 80 composure and lack of curve meaning finesse isn't an option and sometimes he can miss easy chances when under pressure from keeper or defender. I find him better from 20yards than 10yards and i just hit everything hard, he's great from the right side across the keeper.
His dribbling is excellent on top of the pace he has 99 agility and 97 balance with 96 control and 99 dribbling so he feels really smooth on the ball and is great at twisting and turning, plus he's quite small so he moves in and out of tackles really well, he also has 86 strength so this with the balance means he can hold off a lot of fullbacks when through.
His passing isn't the strongest and if you cross a lot the lack of curve and 89 crossing and 80 long passing may be an issue for you but i tend to play on the floor so its not been a problem for me, however he has 93 short passing and for pass and move football these stats are perfectly good enough
He's also not very tall so if you want to go for the lobbed back post cross a lot then he probably isn't the option for you either but he has 99 volleys and has scored a few belters for me from crosses.
If you want a quick winger to get in the box and score you goals then he's a fantastic option, but if you want him to cross it and you want to cross to the backpost for him then i'd avoid,