Recent Bandai Namco anime tie-ins haven't been great, and the anime from which this game is taken is "meh" at best, but the various trailers gave a Kingdom Under Fire vibe to Grancrest Senki (or Record Of Grancrest War), so I steeled my will and clicked that "buy" button.
And this is easily the best anime tie-in done by Bandai Namco in recent times. Not that this is a huge accomplishment, but at least the game doesn't feel like it's done with spare change found below vending machines. The first impressions is that Grancrest Senki looks good, with a lot of unit and environment detail. The game does struggle to reach 30fps on a standard PS4, but at the very least the framerate doesn't fall to single digits in the busiest moments. However the more you play, the more you realize that the whole game, from interface to in-game battles, is actually overloaded with details. The interface isn't particularly hard to navigate but there isn't enough contrast between active menus and what's below, almost every single button on the controller opens some kind of menu (it's as if developers where aiming for a PC release and then they realized it was meant for a console), and the world map could have used a less saturated look.
In fact, the whole game could have used more subdued colours: on the battlefield it's not hard to distinguish between army units and background objects, but chaos beasts blend almost completely with the background due to their colour palette. The interface during battles could have used some serious decluttering and brigther colours when issuing orders. The overall impression is not terrible, but it takes some time to get used to the whole interface and how pad buttons are used in various phases of the game or different menus.

But how is Grancrest Senki structured? Well, it follows the events of the anime series, and probably this will be the game's biggest flaw. You play as Theo Cornero on a quest to liberate his country of Sistina, which quickly derails into stopping a continent-wide war and save all nations from a conspiracy.
The game is divided into planning and battle sections.
Planning sections play almost as a 4X game: you select battles to play, assign troops to leaders, leaders to strongholds, change taxes, equip items to leaders. These sections run on a timer, when that is up the next anime-related event is forced upon you. If there are no other battles to play, or those available are at higher (or lower) level than your troops, you can skip directly to the next anime event. Now, I've just played a couple of hours and maybe (maybe) the game will open up with less restrictive events; I doubt that, and I'd have strongly preferred a more open-ended approach if the game entices you with this kind of structure. Alas this doesn't seem the case, but at least Grancrest Senki isn't a dry recreation of the anime with just action sequences.

On the field you control Theo directly and can bring up to five leaders with you. Leaders belong to various classes and are escorted by different kind of troops. You can order leaders around the battlefield (unless they're stuck in anime-dictated event), which is done in semi-realtime: time slows down but everything will still continue to carry out whatever they are doing. This is where the interface could have used some more refinement, especially when assigning positions to support troops or trying to position ranged units: the camera is always the same, with position and zoom level for movement not optimal for battles and vice-versa. The semi-realtime mechanic is a nice touch but at time you're battling in directing troops how you want or have the game register the support position you'd like; at times I've found difficult to have healers and mages stay back or to have fighters attack enemies rather than just reaching a location. It's the beginning of the game and I have to get used to its quirks, but hopefully things won't become overbearing in later battles, especially as I'm nowhere near done describing how battles work.

Battles are action sequences in which Theo is under you direct control: Theo has two attacks (for ground and air combos), can guard (and of course there's a timely guard mechanic), special attacks, and of course direct attack orders for other leaders. Engaging enemies is straightforward, you just mash one of the two attack buttons. Just be sure to engage troops your leaders aren't weak against, there's a weapon triangle akin to Fire Emblem in place. Theo can order leaders to execute specific attacks that could lead to combo chances and do massive damage to the enemy giant crab (haven't met one yet but there have been giant wolves and bees, so not I'm not ruling it out). Leaders have their own attack gauge and you can queue attacks as long as there's some meter left. You also need to keep in mind execution times (especially with mages and healers), mind their location, protect support units, and so on. Grancrest Senki is a very busy game not only graphically and you are required to multitask at almost every single moment. It's very demanding with oh-so-many things to keep track of and the language barrier, and at times I was wondering why things wouldn't work out as I wanted, but it's not overwhelming.

Grancrest Senki (which, by the way, is penned by the same guy behind Record Of Lodoss War) is avery ambitious game, let's see how it holds up in the long run.