Checked on Scienza and looks like although born in Brazil and therefore eligible, looks like at one point he opted for Luxembourg, not sure if that makes him ineligible for Brazil or not.
"Because his ancestors held Luxembourgish citizenship, Scienza was able to become a naturalized citizen. However, according to FIFA regulations, he would have to live in the Grand Duchy for five years to have any chance of playing for the FLF national team. "I would be willing to give up my Brazilian citizenship if I could play for Luxembourg," he told the Tageblatt newspaper four years ago."