Haaland scored the only goal of the game as City made it three wins from their opening three league matches, while also reaching 300 club goals in his career.
Fernandez and Ndiaye were both handed their City debuts following their deadline-day arrivals, with the club spending heavily to strengthen their squad after the departures of several experienced players.
Fernandez joined from Chelsea for 125 million pounds, while Ndiaye arrived from Everton for 65 million pounds.
Haaland was particularly impressed by what he saw from the pair and believes they showed exactly why City moved to sign them.
"I think they did a really good game, both of them," Haaland said.
"Enzo came in and did really well on the goal and had some chances actually; he could have scored. He did well.
"And Ndiaye, you can see his quality straight away. The way he dribbles past players, just gliding through. It was amazing to see.
"There's a reason why they were bought by us, because they have quality."
Haaland believes the next challenge for the newcomers is to settle quickly and build an understanding with their new teammates.
"For them it's about getting into the team as quickly as possible and getting the rhythm in," he added.
City now turn their attention to the Champions League, with a trip to Portugal to face FC Porto at the Estadio do Dragao on Tuesday.
