Looking at Nintendo's shipment figures for Super Mario Maker 2, it seems the voucher programme they're running is likely pushing digital sales in Japan - I've seen estimates that Super Mario Maker 2's first week sales were 33 to 40% digital.
As others have pointed out, if Three Houses has a similar digital ratio, you're looking at a combined physical/digital first week of around 200,000. Still a ~40k step down from Awakening and a big step down from Fates, but in Fates's case the comparison isn't very fair. Fates had three retail SKUs in Japan and some customers will have bought both Birthright and Conquest. Plus, 3DS had an install base of around ~19 million when Fates came out, more than double the 8 million install base Switch has right now.
I'd say 200k is still on the lower end of what people would have expected, but my guess is lower Japanese sales will be more than made up for in other markets. I'm still expecting Three Houses to top 3 million globally and become the best-selling Fire Emblem game.