According to Globo Esporte, the Portuguese champions interfered in negotiations between Palace and Flu for the 20-year-old.
Evanilson is already on his way to Porto ahead of his medical and contract signing.
Fluminense confirmed the sale today without naming the Portuguese club, which is Porto.
Crystal Palace then arrived on the scene and were willing to loan Evanilson straight back to Fluminense.
But his immediate future will be with Porto rather than the Premier League.
Highly-rated Evanilson was Fluminense’s deputy top scorer in 2019 with nine goals in 24 appearances.
Because of his split ownership, Fluminense will only receive 30% of the reported €9m transfer fee for Evanilson.