Hi. I have such a problem. I play Diablo IV on PlayStation 5 and PC. On PC, I discovered the whole world, which is why I have a problem with getting trophies on PlayStation zs discovering the whole world. I repeated the whole process only on the PlayStation, unfortunately the trophy didn’t pop up.
In achievements it is marked as earned.
Its cross play which means whatever you earn on the Pc carries over to the Ps5.
in-game achievements are included. You didn’t get the trophy for visiting the whole world
Yeah you’d expect the trophy to base off that in game achievement so as soon as you loaded up the PS5 game it should have pinged really.
Unfortunately, the trophy didn’t pop up. I have no idea what to do.
You could try to do it on Hardcore I guess? That has its own set of achievements I think. Not 100% on that though so worth checking.
thanks for the advice, i’ll try it for sure. I will also add that I tried to discover the map a second time. unfortunately it didn’t.
I have the same problem from ps4 to ps5 throphy got locked
Problem exists on PS4 and PS5. I have one missing trophy on each of the consoles (different trophy) - the ones needed to achieve platinum trophy. And these trophies are now unachievable/blocked.
Problematic trophies:
[got it on PS4, can’t achieve on PS5]
Chaotic Whispers
Open 10 Caches of Chaos from the Tree of Whispers.
[got it on PS5, can’t achive on PS4, even with 25 kills on PVP]
Master Combatant
Get 5 PvP kills.
The other thread had a post one day ago. And during play for me nothing unlocked, as i often update everything. Seems not fixed in latest update either.
same problem here. I hope they will solve it soon. 
I play ps5 exclusively, same thing. One day I was rumbling about and noticed a tiny fuzzy are, rode through and the trophy popped. I honestly wish I could remember where, but that’s likely what’s happened for you.
I have The same issue with The Chaotic whispers achievement. No progression on PS5