Eastasiasoft has announced that Murder By Numbers will be available as physical copies with both standard and limited versions of the game on Twitter. You can expect them to arrive in September later this year.
Keep in mind that with everyone being on lockdown, things like release dates are prone to change. Check the official website for updates on the game and when it will release over the upcoming months.

They also released a tweet confirming it’s physical copy release dates:
The official website also gives us a glimpse at different things people get in the limited edition of the game. It comes with a physical copy of the game (along with a manual) as well as a numbered certificate letting you know exactly which one you got. The order also comes with an art book and a sheet of S.C.O.U.T. stickers. And last, but not least, the soundtrack compressed into two CDs with tracks from the game are on it. This will be a region-free release, with both English and Japanese subtitles available.
Murder by Numbers is an adventure game along the lines of the Ace Attorney series with Picross-style nonogram puzzles, with intriguing characters designed by Hato Moa. Masakazu Sugimori, who composed the Phoenix Wright: Ace Attorney soundtracks, put together its soundtrack.

Murder by Numbers is already available digitally for the Nintendo Switch and PC. The Murder by Numbers physical copies will be released sometime in September of 2020. Playasia is the only retailer listed that’s able to sell them.