On first glance it appears they implemented 5e with minor changes to classes (ranger/rogue the most changed), but once the combat starts you can't call it 5e anymore. Their 'minor' changes that accoridng to them were necessary to make it work in a video game have such deep rooted effects that they completely broke the action economy. Every change they made are based on their DOS-philosophy and are absoutely not necessary to make it work in a digital medium. Action economy, surfaces, far too many advantages/disadvantges, grenades and special arrors being the most common thingin the game, barrelmancy...

You will see that a significant part of the AI's action are based on Larian's changes - in other words they unbalanced the game by adding stuff that is more efficient than D&D 5e options you can do. So I call them out on either lying to the players - or worse to themselves - that those changes were necessary. The made the game unbalanced and worse. Sprinkling D&D with DOS2 didn't improve anything and pretty much all the changes are bad as of now and their ripples will disrupt the next classes as well as higher levels even more than they already did.