You know the answer to this question, they all suck dick. But except for Solasta, they're all RTWP games, destined to have retarded combat because they were produced in an age where retarded publishers wanted every game to be Diablo, and the RPG genre had to suffer for it.
Ok, throw in PKM and WotR. Are they better?
What do you classify as good, or difficult, or well-designed combat encounter?
My point is you already know what system the game uses and how it works, so what's left is designing the encounters uniquely. If you are super experienced with D&D games you know the synergies, the counters, and the "meta". Designing encounters for this kind of player just turns into an exercise for the designer to one-up you in his munchkinism, while still allowing you a narrow margin within which to "beat" him, because after all, you're the player.
And much to no-one's surprise, this mainstream oriented BG3 doesn't include the equivalent of Unfair difficulty from the Pathfinder games.
The reason I never gave Tactician a try is exactly because I've spent enough time in other games, trying to find satisfaction in the max difficulty level. By now I know that there are RPGs where it makes sense to try harder difficulties (from the start), ones where a harder difficulty is a good idea for a second run, and ones where the higher difficulty is badly implemented and only tests one's autism. My estimation is that BG3 is in the best of cases in the second category. But for a first run, I'd rather go with the difficulty the designer expects the average player to take and has tested the most.