Richarlison joined Watford from Fluminense in 2017 and went on to score five goals and register five assists in the first half of the season, before failing to add to that tally in the remainder of the campaign.
This season, the 21-year-old has scored 11 goals in his 27 appearances, setting up two goals for his team-mates.
Richarlison received his first call up for his country in August 2018, making his debut against the United States the following month.
Since then, he has scored three goals at international level, with two against El Salvador and one against Cameroon.
Everton boss Marco Silva is under intense pressure at Goodison after a poor run of form has left Toffees fans running out of patience.
Former Blues striker Kevin Campbell has outlined why he thinks Silva is struggling.
“Everton have spent, the problem everybody’s got is Marco Silva has got players from three different managers,” he told Love Sport Radio.
“Now he’s come in he’s had to buy players and it’s all a bit of a much of a muchness.