The 20-year-old was recently the youngest member of Canada's squad at the World Cup, the Maples Leafs making their first appearance at the tournament since 1986.
Despite the disappointment of his nation losing all three fixtures in Qatar, Kone was able to make substitute appearances against each of Belgium, Croatia and Morocco.
With nine caps now to his name, the prospect is regarded as a potential star for the future, and it appears that he has now chosen to continue his career in Europe.
According to transfer expert Fabrizio Romano, the Hornets are in line to win the race for Kone ahead of the January transfer window.
However, while Montreal are seemingly due to receive a club-record fee for one of their players, the deal is not due to be straightforward with regards to Kone's time at Vicarage Road.
As well as Romano, reports elsewhere have indicated that Kone will spend the second half of the season in the Championship before moving to Udinese in the summer.
The two clubs are owned by the Pozzo family and have a history of trading players being the teams, with two such arrangements occurring in the summer.
Adam Masina made the permanent switch to Udinese, while the Serie A side signed Hassane Kamara before immediately loaning him back to Watford for 2022-23.
Nevertheless, head coach Slaven Bilic will welcome the arrival of Kone as he bids to earn Watford a return to the Premier League after last season's relegation.
As it stands, Watford sit in fourth position in the Championship, five points adrift of the top two, with Bilic collecting 19 points from his 11 matches in charge.
Kone, a player who can play in each central-midfield role, made 28 appearances in the recent MLS campaign, contributing two goals and six assists.
He leaves Montreal with a total of 32 outings to his name, with each of his nine caps for his country being earned since March.