Kenedy first caught the public's eye after a good spell in 2013 Copa São Paulo, a traditional Brazilian youth football competition which earned him a call-up to Brazil's U17 side. It also earned the forward some appearances as a substitute for a struggling Fluminense team, which was relegated on the pitch but maintained in Brazil's first division in the courts.
In 2014, Kennedy's perceived impact on the pitch was quite negative, as his apparent unwillingness to "do the simple thing" made part of the supporters turn a bit on the player. It went back and forth until Kenedy, after talking with Fluminense's captain Fred (yes, the World Cup Fred) and the board, came forward to apologize for his attitude.
2015 started badly for Fluminense, as their long-time main sponsor Unimed dropped out after political struggles between the club and the company presidents, and Unimed's financial issues. With little to no money to make transfers and keep core players like the Argentinian Dario Conca, the club had to look to its famed Xerém academy. It would mark the breakout (half) season of Gérson and Kenedy.
Kenedy was clearly the faster and stronger of the young duo. His bursting runs and left-footed prowess quickly made pundits associate him to Zenit's Hulk, although one could argue that Kenedy is more tactically flexible position-wise. He also isn't shy to try tricks in his dribbling, even though it annoyed many Fluminense supporters whenever those tricks failed and resulted in lost possession.
It is quite difficult not to make comparisons between Kenedy and Hulk whenever you watch him play, especially considering how both are natural right wingers with a liking to cut inside and shoot from the box or from afar with their powerful left foot. Against players his age, Kenedy was able to beat them thanks to his above average speed and a low center of gravity, as well as his physical stature. It became a bit more difficult for him to replicate the dominant showings at the senior football level, but he still terrorized his markers with his bullish ruins.
He is far from perfect, though. With 5 goals in 1600+ minutes across 40 appearances - or 0.27 goals for every 90 minutes he was on the pitch - he doesn't have good numbers for an attacker, even though 26 of his appearances were as a substitute.
One can see that he doesn't use his physical tools to its fullest, yet, and to top it off, he is sometimes overly reliant on them. It wasn't uncommon to see him being beat by a defender when he was chasing a ball either due to his positioning or simply giving up on getting it. He also isn't the most skilled dribbler in tight spaces, which might be one of his major struggles to adapt to European football after being so accustomed to play in a league which gives players lots of space to work.
He is also a bit inconsistent, zoning in and out of games. Sometimes he will look like a world-beater; in others, he will look like a common one. But it can all be worked on if he's given playing time and proper coaching - the latter something he and other Brazilian players sorely miss whenever they come to play for professional teams.
If I were to make a guess on his future, I'd say he can come around as Chelsea starting material in a few years. He still has a lot to work on as he's a bit rough around the edges but he certainly has the potential to be a very good player. Hopefully everything will work out for him. If it doesn't, we can take solace in the fact that he only cost £6.3 million, and making a profit on top of it shouldn't be that difficult. Just look at Mo Salah.