On the whole the Pentax K-1 II has worse image quality than its predecessor, and its autofocus performance and video capabilities also lag greatly behind the competition (compared to Sony a7 III, Nikon D750 and Nikon D850).
Conclusion from DPReview:
The Pentax K-1 II features a stabilized 36MP Full Frame sensor and one of the toughest-built bodies on the market. Jam-packed with unique features to aide those shooting under harsh conditions, we’re big fans of its many control points and great ergonomics. However, its image quality is actually worse than that of its predecessor. Its autofocus performance and video capabilities also lag greatly behind the competition.
The Pentax K-1 Mark II DSLR camera is now in stock and shipping at major US stores: