The Red Devils moved to put a €55 million (£47m/$60m) deal in place for the 25-year-old playmaker during the January transfer window.
Fernandes has hit the ground running in English football, with little adjustment period required by the Premier League rookie.
United, having tracked a long-standing target for some time, always hoped that the fresh face could make an immediate impact – especially with Paul Pogba enduring form and fitness issues.
The big-money recruit has not disappointed, with Fernandes helping to reignite a spark in Ole Gunnar Solskjaer’s side.
He has been leading by example, dragging others along with him, and has been showered with plaudits on the back of United forcing their way into contention for a top-four finish and major silverware at home and abroad.
Cole is among those to have been impressed by Fernandes, with the 1999 Treble winner hailing the qualities that have been re-established in a Red Devils team that had been struggling for consistency.
He told the Manchester Evening News: "Mentality, that’s massive in football. Confidence as well. Once you’ve got your confidence people start believing in each other.
"We can talk about Fernandes coming in, he’s done extremely well and it’s looked like he’s galvanised the rest of the players as well to start playing their A-games."
Pressed further on whether one player can impact an entire squad, Cole added: "He’s done it, he’s started to bring the best out of a few of the other players, which is important."
With Fernandes pulling the strings, questions of Solskjaer’s future at Old Trafford have started to fade.
He is now being backed to get the time required to complete a rebuilding project, with Cole among those to see cause for optimism.
The ex-England international added on a former United team-mate and how the 2019-20 campaign could play out if competitive action resumes after the coronavirus pandemic: "Ole is starting to implement his plan now, which is good.
"If it does get itself upright again hopefully they can finish really strongly, there’s a good possibility they can still finish in the top four and Champions League football is going to be needed for a club like Manchester United."