People have the game, though this person claims they're not press or anything and aren't bound to an NDA. I've removed the hidden story trophies from this list, they're not super spoilery as it's mostly just "Completed X Mission" but it could imply things from mission titles and stuff. You can go here to find them yourself. The other trophies are below.
List looks to confirm there are 70 story missions in the game, typical length of a Rockstar game.
Platinum - Legend of the West - Legend of the West
Silver - Lending a Hand - Complete all optional Honor story missions.
Gold - Best in the West - Attain 100% completion.
Silver - Gold Rush - Earn 70 Gold Medals in Story missions.
Bronze - Friends With Benefits - Complete a Companion Activity in each camp.
Bronze - Hobby Horse - Play all mini games.
Bronze - Breaking and Entering - Recover the stash from 4 homesteads.
Bronze - Take From the Rich - Rob or loot $250.
Bronze - Give to the Poor - Donate $250 to the gang tithing box.
Bronze - Pony Up - Spend $5000 across all shops.
Bronze - Extreme Personality - Reach maximum or minimum Honor level.
Bronze - Western Stranger - Complete 10 Stranger mission strands.
Bronze - Bountiful - Survive 3 days holding a bounty of $250 in all states.
Silver - Collector's Item - Complete one of the Collectable strands.
Bronze - Errand Boy - Deliver 5 camp companion item requests.
Bronze - It's Art - Find a permanent home for the squirrel statue.
Bronze - Self Sufficient - Craft 30 unique items in Story Mode.
Bronze - Skin Deep - Skin every species of animal in Story Mode.
Bronze - Zoologist - Study every animal across all states in Story Mode.
Bronze - It was THIS Big! - Catch a fish weighing at least 16 lbs (7.3 kg).
Bronze - Locked and Loaded - Upgrade each available component for a single sidearm or longarm weapon.
Bronze - Grin and Bear it - Survive 18 bear attacks and kill the bear each time in Story Mode.
Bronze - Trusty Steed - Reach max bonding level with a horse.
Bronze - Breakout - Red Dead Online: Complete the Intro.
Bronze - Series Major - Red Dead Online: Take part in a Series.
Bronze - Gun For Hire - Red Dead Online: Accept 10 Free Roam missions from characters around the world.
Bronze - Eventful - Red Dead Online: Play 5 Free Roam Events.
Bronze - Buckle Up - Red Dead Online: Achieve 5 gold belt buckles from awards.
Bronze - The Real Deal - Red Dead Online: Achieve MVP 3 times (in a round with at least 4 players).
Bronze - Horses for Courses - Red Dead Online: Concurrently own 5 horses.
Bronze - Getting Started - Red Dead Online: Reach Rank 10.
Gold - Notorious - Red Dead Online: Reach Rank 50.
Bronze - All's Fair - Red Dead Online: Successfully counter a rival Posse's Free Roam mission.
Bronze - Home Comforts - Red Dead Online: Purchase 5 camp improvements.
Bronze - Non-Regulation - Red Dead Online: Craft 25 pieces of ammunition.
Bronze - Posse Up - Red Dead Online: Form a Persistent Posse.
Bronze - Master Craftsman - Red Dead Online: Craft 20 items (excluding ammo).
Bronze - Butchered - Red Dead Online: Sell 20 items to the Butcher.
Bronze - Picked to Perfection - Red Dead Online: Pick 25 Herbs.
Bronze - Strength in Numbers - Red Dead Online: Complete a Free Roam mission as part of a Posse with at least 2 members.
List looks to confirm there are 70 story missions in the game, typical length of a Rockstar game.
Platinum - Legend of the West - Legend of the West
Silver - Lending a Hand - Complete all optional Honor story missions.
Gold - Best in the West - Attain 100% completion.
Silver - Gold Rush - Earn 70 Gold Medals in Story missions.
Bronze - Friends With Benefits - Complete a Companion Activity in each camp.
Bronze - Hobby Horse - Play all mini games.
Bronze - Breaking and Entering - Recover the stash from 4 homesteads.
Bronze - Take From the Rich - Rob or loot $250.
Bronze - Give to the Poor - Donate $250 to the gang tithing box.
Bronze - Pony Up - Spend $5000 across all shops.
Bronze - Extreme Personality - Reach maximum or minimum Honor level.
Bronze - Western Stranger - Complete 10 Stranger mission strands.
Bronze - Bountiful - Survive 3 days holding a bounty of $250 in all states.
Silver - Collector's Item - Complete one of the Collectable strands.
Bronze - Errand Boy - Deliver 5 camp companion item requests.
Bronze - It's Art - Find a permanent home for the squirrel statue.
Bronze - Self Sufficient - Craft 30 unique items in Story Mode.
Bronze - Skin Deep - Skin every species of animal in Story Mode.
Bronze - Zoologist - Study every animal across all states in Story Mode.
Bronze - It was THIS Big! - Catch a fish weighing at least 16 lbs (7.3 kg).
Bronze - Locked and Loaded - Upgrade each available component for a single sidearm or longarm weapon.
Bronze - Grin and Bear it - Survive 18 bear attacks and kill the bear each time in Story Mode.
Bronze - Trusty Steed - Reach max bonding level with a horse.
Bronze - Breakout - Red Dead Online: Complete the Intro.
Bronze - Series Major - Red Dead Online: Take part in a Series.
Bronze - Gun For Hire - Red Dead Online: Accept 10 Free Roam missions from characters around the world.
Bronze - Eventful - Red Dead Online: Play 5 Free Roam Events.
Bronze - Buckle Up - Red Dead Online: Achieve 5 gold belt buckles from awards.
Bronze - The Real Deal - Red Dead Online: Achieve MVP 3 times (in a round with at least 4 players).
Bronze - Horses for Courses - Red Dead Online: Concurrently own 5 horses.
Bronze - Getting Started - Red Dead Online: Reach Rank 10.
Gold - Notorious - Red Dead Online: Reach Rank 50.
Bronze - All's Fair - Red Dead Online: Successfully counter a rival Posse's Free Roam mission.
Bronze - Home Comforts - Red Dead Online: Purchase 5 camp improvements.
Bronze - Non-Regulation - Red Dead Online: Craft 25 pieces of ammunition.
Bronze - Posse Up - Red Dead Online: Form a Persistent Posse.
Bronze - Master Craftsman - Red Dead Online: Craft 20 items (excluding ammo).
Bronze - Butchered - Red Dead Online: Sell 20 items to the Butcher.
Bronze - Picked to Perfection - Red Dead Online: Pick 25 Herbs.
Bronze - Strength in Numbers - Red Dead Online: Complete a Free Roam mission as part of a Posse with at least 2 members.
