Sky Sports News understands the deal could be worth in the region of £50m

Everton and Watford are in advanced talks over a deal to sign Richarlison
Everton are in advanced talks to sign Watford forward Richarlison in a deal which could be worth a £50m, according to Sky sources.
Richarlison, 21, signed for Watford last summer for £13m from Fluminense when current Everton manager Marco Silva was in charge at Vicarage Road.
The Brazilian forward made a big impression on his arrival to the Premier League, scoring five goals in his first 12 appearances.
A £50m deal would see Richarlison become Everton’s club-record signing, overtaking the £45m the Toffees paid for Gylfi Sigurdsson last summer.
Source: http://www.skysports.com