Here is the full list of all 48 Sonic Forces achievements. It takes around 25-30 hours to unlock all of the achievements on Windows.
Collected all Red Star Rings in Shadow's Story.
Defeated 10,000 enemies
Collected all Number Rings
Utilized the Rental Avatar function
Collected Silver Moon Rings three times
Collected 30 Wispons
Cleared all EX Stages
Collected all Red Star Rings
Collected Number Rings three times
Completed 5 Daily Missions
Collected a total of 10,000 rings. (All Rings held at the end of the stage will be counted.)
Completed your first SOS Mission
Defeated 5,000 enemies
Created your second Avatar
Used the Closet
Cleared all Secret Stages
Achieved a soldier's highest honor
Collected 10 Wispons
Restored peace to the world
Defeated Infinite
Defeated 1,000 enemies
Turned the tide of the conflict
Drove off Infinite again
Cleared Stage 1
Created an Avatar
Defeated Zavok
Drove off Infinite
Drove off Eggman
Liberated a world
Changed Wispons for the first time
Equipped a part in every slot
Collected 50 parts
Collected 100 parts
Completed 3 Daily Missions
Collected all Silver Moon Rings
Collected a total of 50,000 rings. (All Rings held at the end of the stage will be counted.)
Collected a total of 100,000 rings. (All Rings held at the end of the stage will be counted.)
Achieved highest honors with all races
Made it into the rankings
Collected all Wispons
Collected 500 parts
Collected all parts
Completed 10 Daily Missions
Completed 5 SOS Missions
Completed 10 SOS Missions
Completed all Challenge Missions
Collected all Number Rings in Shadow's Story.
Collected all Silver Moon Rings in Shadow's Story.