Item description:

I have no way to see if these work, but they should pop because all of the save slots were made before performing the final step necessary to obtain the trophy. This is a platinum save so other trophies may pop.

Save 03
Pursuit of Knowledge: Read the datalog in front of you and the trophy should pop.

Save 04*
Through the Dimensional Rift: Omega should be right in front of you once loaded. If not, try restarting your PS4 and load a different save slot before trying this trophy again. I can't give you a clear strategy on how to beat him. The food Seasoned Midgardsormr is already active. Google around for how to beat it, see which strategy works for you. You'll have the majority of the equipment, weapons, and several high-level thunder magicite spells. There are more than enough restorative items also.

Save 07*
Tri-Headed Triumph: Cerberus will be right in front of you once loaded. If for some reason he isn't, try restarting your PS4 and load a different save slot before trying this trophy again.

Save 08
Maiden Voyage: Get on the boat.
Narwhal Watching: Sail around. You'll get a cutscene with some seagulls. Sail towards them and try to follow them. Eventually, another cutscene should pop with Bismarck, along with the trophy.

Save 09
Speed Daemon: You load in front of the final course. Complete it; you're given more than enough time.

*If either of these bosses do not show up and restarting doesn't work, you'll have to go to a rest area, travel to the past or Altissa, save while there, quit to the main menu, load the new save you made, and head back to the present. The boss should be loaded now. Alternatively, you could just wander around Insomnia looking for a monster. That should force anything else that should be up to spawn.

The other save slots are insignificant.