Richarlison has passed his medical with Everton ahead of his move from Watford, Sky sources understand.
The deal is expected to be finalised on Tuesday morning.
The 21-year-old winger, who was signed by Watford last summer when current Toffees boss Marco Silva was in charge at Vicarage Road, returned home early from Watford's pre-season training camp in Austria.
Richarlison joined Watford from Fluminense for £13m last August and impressed in his debut Premier League season, scoring five goals in his first 12 appearances.
Everton are yet to sign a player this transfer window, though have also been linked with Barcelona defender Lucas Digne.
Players including Wayne Rooney and Ramiro Funes Mori have departed Everton this window, and England U21 international Ademola Lookman is also reportedly set to leave the club.
Silva refused to comment on potential signings when speaking to Sky Sports News at Everton's training camp in the Algarve, but he is expecting a busy time in the coming weeks for both incomings and outgoings at Goodison Park.
Sign Richarlison for £8.6m
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