I actually found myself digging into this a few weeks back. From what I can gather, the Berserk guidebooks that focus on the video games themselves are a mixed bag, and 'updated' is the tricky part. The 'Berserk Official Guidebook' from the late 90s, tied to the Dreamcast game, is obviously outdated. The more recent ones, like the 'Berserk: Millennium Falcon Arc – The Holy Evil War' book, are primarily manga art/commentary compilations, not gameplay manuals.
If you're after something that covers the 2016/2017 'Berserk and the Band of the Hawk' musou game from Koei Tecmo, your best resource might not be a physical guidebook at all. The official strategy guide for that title was digital or region-specific, and most up-to-date mechanic breakdowns live on wikis and dedicated fan forums now. The physical editions feel more like archival collectibles than functional guides for current gameplay.