Done on a phone that is not rooted running Termux, termux-usb, usbredirect, and QEMU --> "cryptsetup luksFormat /dev/sda1" and "cryptsetup luksOpen /dev/sda1 v1" and "mkfs.ext4 /dev/mapper/v1" and "mount /dev/mapper/v1 /root/1" where "/dev/sda1" is a partition on a USB flash drive ("dev/sda") plugged in the phone:
https://github.com/termux/termux-packages/issues/19635 (cryptsetup is in Update-6 and Update-7, see also "Connecting a USB device to QEMU using termux, termux-usb, usbredirect")