The 16-year-old has caught the eye in the Dortmund youth ranks and has also been registered in the club's UEFA Champions League squad.
The Cameroon legend spoke highly of Moukoko this week and feels he could be the future of the Blaugrana.
"There is a young player at Borussia Dortmund. His name is Youssoufa Moukok," Eto said at the LaLiga Santander Ambassadors Gala this week.
"He is 15 years old and the next big player for me after Messi.
"As Lionel is getting older, we could prepare well for the future at Barcelona.
"With Antoine (Griezmann) and Youssoufa on the front line, the team would be in a great position."