The only safe "single-device" method requires an unlocked bootloader to begin with (Catch-22).
Here’s a full, realistic review of the process and concept behind — a topic that pops up in Android modding communities. unlock bootloader via termux
He cloned the Heimdall source code.
: If your host device does not support USB OTG or if the cable is "charge-only," Termux will not see the target device. The only safe "single-device" method requires an unlocked