Amorim officially became Man United's new head coach on Monday, with Ruud van Nistelrooy's time as interim head coach ending on Sunday after leading the Red Devils to a 3-0 success over Leicester City.
The 39-year-old's first match at the helm will come against Ipswich Town on November 24, and he is currently settling into his new surroundings, having arrived in Manchester on Monday.
Fernandes will not meet with Amorim until next week, as he is currently with the Portugal squad preparing for their UEFA Nations League matches against Poland and Croatia.
The attacker did not play under Amorim at Sporting, as he left the Green and Whites for Man United in January 2020, with Amorim taking charge of the Lisbon giants in March 2020, but Fernandes has kept a close eye on his former club.
Fernandes says Amorim "did something very special at Sporting"
"This is the right moment for him to come, bring his energy, his qualities and his knowledge of football because he did something very special at Sporting," Fernandes told MUTV.
"I watched almost all of the Sporting's games. [Amorim] is someone who brought the excitement back to the club. He brought a lot of good things to the club and hopefully, he can do the same here because sometimes a person can change the energy of a space if it's the right moment.
"They were about 20 years without winning the league, he got them back to winning the league and he did it twice in four years with a really [young] team in a moment of change. Hopefully, it can be a successful moment for us.
"He's done really good things tactically, from what I've seen. Obviously, he can't transform what he's done in sporting to here. We have different players and different ways of playing. But I'm sure the idea of football he has, independent of the way he wants to play, will bring us success.
Fernandes has hailed "great character" Amorim
"For me what stands out for me is the connection he has with players. When the manager is going from your club in the middle of the season with all the things they have still to win, you see the way they say goodbye to him, the way they make him feel part of the team and the way they treat him, it shows he's a great character and he is someone that gives his all to the players.
"I have seen many moments where players were struggling and he goes to the press conference to defend his players to give them the best opportunity to shine. He had a really young team so he needed to do that, hopefully, he can do the same with us."
Amorim left Sporting with a record of 164 wins, 34 draws and 33 defeats from 231 matches, winning five trophies, including two Primeira Liga titles.
The head coach has also overseen an excellent start to the season for the Green and Whites, with the team winning all 11 of their league matches to sit at the top of the Primeira Liga table, six points ahead of second-placed Porto.
Sporting have also been in excellent form in the Champions League this season, picking up 10 points from their opening three matches of the season to sit second in the overall table.