The Argentine has committed to moving to Strasbourg's Premier League partners at the end of the season.
Advertisement
Advertisement
Transfer expert Fabrizio Romano is reporting he has given his word to Chelsea and agreed to their personal contract terms.
The 21-year-old, who is also on the wish list of Bayern Munich and Real Madrid, is under contract at Strasbourg until 2029.
There was little chance of Barco moving anywhere beyond Chelsea thanks to the relationship between the two clubs.
Barco originally moved to England with Brighton, but failed to settle on the south coast and was sold to Strasbourg last year.