The 19-year old attacker, who signed with the Mariners in 2019, will join the Primeira Liga club for an undisclosed fee and complete a medical upon arrival.
Silvera was one of the few bright lights in an otherwise forgettable season for the Mariners.
Pacos de Ferreira finished 13th last season, and have played all but one of their last 15 seasons in the first division.
Silvera won't be the first Aussie at the club, with Awer Mabil, Dylan McGowan and Jason Davidson having all spent time with the club.
Silvera couldn't hide his excitement over the move.
“It feels amazing to be moving to Europe. I feel like the football in Portugal will suit my style and I will be working hard to succeed over there,” he said.
“Over this past year I feel as though I’ve grown and developed so much as a footballer and I can’t wait to take this next step forward in my career.”
“I have to thank all the coaching staff for having faith in me and giving me a chance from day one in the FFA Cup and then throughout the season.”
“And I want to thank everyone at the club, all the staff, and the players for being a great playing group to be a part of this season.”