Well the party in the gameplays were level 3 tops, so I do not think they have it ready (feats are at lvl 4 minimum)
I think they didn´t show the UI for character level-up. A pity I wanted to take a peek to see what subclasses you can pick.
There's a list out there for subclasses, that are going to be available at the start of early access.
I've noticed in the gameplay videos, that Shadowheart casts Guiding Bolt often. She usually has a weapon and shield equipped when doing so. Guiding Bolt requires a Verbal and Somatic components, how can she cast it without the Warcaster feat? I'm not complaining, just trying to figure out Larians spellcasting system. It makes a huge difference for my planned spellcaster builds.
Shadowheart is a cleric, and clerics(and paladins) could bear the holy symbol in his shield. And as RAW, you can use the hand where you have your holy symbol or druidic/arcane focus or bard instrument/weapon focus to make the somatic components of a spell. So she can cast spells with somatic components with weapon and shield.
Sc:
https://www.sageadvice.eu/2015/01/04/holy-symbol-on-shield/That only applies if there is a material component, which
Guiding Bolt doesn't have. That's what the
Warcaster feat is for.
That said, I do not think they are going to implement fully all the spellcasting rules: the components in the component pouch, holy symbols, etc
Warcaster is still useful for bards or to use spells as your AoO reaction.
I hope they don't. With only 2 ASI/ Feats (except the Variant Human if that makes it in), it makes most other feats less attractive, if you go weapon and shield.
Warcaster is a must then. Five of my nine builds, that are primary Wizards, use weapon and shield. It would definitely still be a useful feat, just not the 4th level automatic choice. More variety in builds, gives more replay value. And I'm going to play this game to death.