The 29-year-old allegedly claimed on social media that the senator, son of former president Jair Bolsonaro, acquired the property without compensation.
According to the allegations, the dispute began after Richarlison refused to sell the island, where he reportedly invested heavily between 2020 and 2021.
The Brazil international also alleged that political influence and legal proceedings were used to secure control of the property.
"I did not want to sell him the island," Richarlison stated in a video.
"Since I refused, these people took advantage of the situation in court."
Bolsonaro swiftly rejected Richarlison's allegations, describing them as "fake news" and a smear campaign.
