The collections are the western counterpart of Namcot Collection, the Switch-only collection due out on the same day in Japan. Most the initial 11 Namcot Collection titles can be obtained through purchasing both collections (excluding Wagyan Land, Star Luster, Family Jockey, and Yokai Dochuki), including the 8-bit demastered Pac-Man Championship Edition.
Here is an overview of Namco Museum Archives, via Bandai Namco:
What is Namco Museum Archives?
Gathering Namco’s hits and long-lost treasures, each volume of Namco Museum Archives features 10 historic arcade hits such as Pac-Man and Galaga, and also includes some classics that were never before released in the west, such as Dragon Spirit: The New Legend and Mappy-Land.
Developed in partnership with B.B. Studios, Namco Museum Archives takes the retro gaming experience to the modern consoles with new features for improved playability, including rewind, save points, and wide-screen support.