@panos_aliartos yes, just start a new game (on the lowest difficulty if you want to do it quickly) - save it to a new save slot and then charge through the main questline only. You should get to England and be able to a raid within 2 to 3 hours.
You can then go back to your old save and play any new content coming out on that one, and delete the new save if you want.

So my one is a less common issue, but there's likely some similaries others may have - also managed to unlock a few so I'll put what I did in case anyone finds it helpful.

I platinumed AC:V on the PS4, then transferred my save to the PS5 - had to do some work, including a speedrun of a new game to get the platinum there, but all ended up without any really issue.

Completed all Season 1 DLC on the PS5, getting all of the trophies, and then loaded that cloud save on my PS4. As a result, everything below are trophies that I had already unlocked on the PS5, but am not able to unlock (or successfully did) on the PS4:

Wrath of the Druids
No
Irish Legend - can't unlock (limited action)
Like a Druid - can't unlock (limited action)
Ireland's Deliverance - can't unlock (story)
Dawn of the Druids - can't unlock (story/limited action)
The Legend of St Patrick - can't unlock (limited action)
All Roads Lead to Dublin - can't unlock (limited action - have tried fulfilling orders with Azar but nothing triggers the trophy)
King's Maker - can't unlock (have done 10+ new Royal Demands but nothing triggers the trophy)
Yes
Double Trouble - triggered when sickles were equipped
Decked Out - triggered when armour was equipped

Mastery Challenges
Yes
All that Glitters
A True Master - both triggered when I achieved gold (not sure if that is required) on a single Mastery challenge (the Wenlocan Wolf challenge is an easy one to do quickly)

The Siege of Paris
No
Know What is Right - can't unlock (limited action)
Yes
Do What is Right - triggered after completing a Rebel mission
We Nobles Three - triggered after killing an NPC (coincidentally, or not, while wearing the Reaper armour and using a Scythe)
Vive la Résistance - triggered after killing an NPC, as above
Future Past - triggered after completing a Rebel mission
Bad Bull - triggered after killing an NPC, as above
Vendange - triggered after killing an NPC, as above
Pat the Cats - triggered after patting one cat in Evreux
Lése-Majesté - triggered after completing a Rebel mission

Tombs of the Fallen
Yes
Spelunker
Crypt-ologist - both triggered after going into the tomb nearest Ravensthorpe, getting to the end of it (you can't interact with anything), leaving and then completing one of Reda's contracts. They triggered once the mission's objective was completed.


Hopefully the ones I got help someone. The ones I couldn't get are all either to do with completing storylines, completing the map (I've attemped to get the small treasures from random NPCs but that doesn't do anything) or completing a list of limited tasks. I've tried things like completing Reda's contracts, Rebel missions and King's Favours, but there's no other quests available at all (I've already done the Isle of Skye, but haven't listed it as there were no trophies).

Update to above - seems to have been fixed with the new patch, traveled from England to Norway and could see and pick up the treasure.

Likewise with this issue, just putting another one out there. I can see where it should be, but there's nothing to interact with at that spot.

Also have this issue (PS4). The stones give the golden shimmer after holding down Triangle, but I don't get any skill points/XP and it can be interacted with again and again.