@katashu The light novel still will take a while to catch up since its being worked on by sol press (slow af translations). but the webnovel is translated up to 113, mitsuha starts her viscountess work around chapter 30.
Conscription is the best method in this time period. Low economic and technical development means a wealth of people to pull from to teach and harden the bodies of. Once they trust her methods from that, she can institute schools and other advancements easier.