I wouldn't expect DW3 tier acting. Based on the Instagram posts from the studio, Voxx, they seem to be really hyped up and excited about dubbing an "epic game" (they haven't said it's DW9 yet but given a few of the actors a part of the studio have already updated their resumes, it pretty much has to be). They also specialize in multilingual dubs, so I'd expect they get the character names right. So no, no Cow Pee.
I'm sad this means no Cristina Vee as Lianshi, and that Kaiji Tang who loves the series isn't involved any longer. But I'm willing to give the new cast a fair shake since they seem legit into it and not just phoning it in.
Never played dynasty warriors, but can someone give me a rundown
It was my understanding that dynasty warriors is rooted in asian history and tradition, so isn't it pretty natural to not want a dub in this type of game?
The thing is that Three Kingdoms era Chinese is so radically different from modern Chinese, let alone Japanese, that having a dub isn't going to affect accuracy much. Samurai games having a dub, yeah, that's an argument one could have as old Japanese from the 11th-19th century is similar enough to modern Japanese. But Han era Chinese is just really different from anything else currently extant, afaik.