I recently purchased WC3 reforged and I am playing on my Macbook Pro 16" and finding missing textures throughout the game. It occurs on the first prologue/training campaign mission - the goldmine has no textures applied. It then happens on at least one or two places in each mission thereafter. I have verified my game files and it found nothing wrong.
We’ve seen a few reports on this issue recently. There haven’t been any patches on the game for a while so it’s odd that this issue has just begun being reported more frequently.
For now the only workaround that works consistently is to revert to the Classic WC3 graphics for these missions.