During this weekend's Tokyo Game Show 2019, a Final Fantasy VII Remake showcase revealed a number of new details about the game, including confirmation of a "Classic Mode" style of battle that can be selected to replace the game's new, mostly-real time combat system.
Default combat in FFVII Remake will resemble the action RPG-style combat system that debuted in FFXV, in that it takes place within the game world (rather than a separate combat arena version of the in-game world, as is standard in classic JRPGs) and occurs mostly in real time. However, whereas the majority of FFXV's combat entails basic attacks and movement abilities with some characters' combat abilities thrown in, FFVII Remake will still have in place an ATB (active time battle) system and the more standard abilities from the original game.
Basic attacks gradually build up the ATB meter, which, rather than determining when a character can act in battle, is now a resource that needs to be spent in order to use abilities. When selecting an ability, the game can be briefly paused (this is called "Tactical Mode") to allow the player time to navigate through menus—essentially the inverse of classic FFVII combat, where navigating through battle menus happened in real time.
However, for those who want a gaming experience closer to that of its predecessor, or those who simply don't enjoy the new combat system, Classic Mode attempts to replicate the experience of battle in the original FFVII. When this mode is selected, characters will auto-attack, building the ATB bar without the need for player input. In classic FFVII, each character's ATB bar simply filled up over time, so while this isn't a 1:1 equivalent, it nonetheless the closest approximation possible within the constraints of the updated combat system.
This allows players to focus solely on menus during battle, queuing up abilities for just when the ATB bar fills up. Even though the function of the ATB bar has been changed, the experience is fundamentally the same, as optimal combat in the original FFVII requires acting with a character the moment their ATB bar is full. Even in its standard combat mode, as shown in the gameplay video screened at TGS2019, battle outside of when abilities are used appears to consist of little more than moving and spamming the attack button. While this potentially could hinder combat to a small extent, given that enabling auto-attacking takes away control from the player, these two modes might not differ so much as they will accommodate for nominally different playstyles.
Source: twitter.com/finalfantasyvii