The Manchester City forward has missed the last three Gameweeks through injury.
The Argentinian has a superb home record this season, with a goal or an assist in all seven of his appearances at the Etihad Stadium.
Aguero produced four goals and an assist over his two meetings against the Hornets.
A return for Aguero would force FPL managers to reconsider their options up front, with the 30-year-old challenging Harry Kane (£12.5m) and Pierre-Emerick Aubameyang (£11.6m) as the go-to premium option.
Man City could also welcome back another big-hitter as Kevin De Bruyne (£9.7m) will also be assessed for Saturday's early kick-off.
Down to only 3.2 per cent ownership, the Belgian can be a big differential pick, with a home match against Crystal Palace in Gameweek 18 to follow.
Part 1: GW17 Selection: Sane backed to keep scoring
Part 2: FPL Show: Is Salah worth the money?
Part 3: GW17 Captains: Kane and Sterling set for home profit
Part 4: GW17 Captains: New role revives Hazard potential
Part 6: GW17 Team news: Wilson owners seek replacements