IMPORTANT NOTE:
Install the initial zip before installing the rom

- Gms/gapps initial zip for axion
- Vanilla initial zip for axion

The initial install zip has the boot and vendor_boot images bundled together.

Also OTA might not work so you might need to dirty flash the zip yourself

You don’t need to fill your slots or flash Android 15 stock beforehand, as the ROMs already bundle Android 15 firmware, unless your device is on anything older than Android 14 May 2024 stock (U1TDS34.94-12-7-5), in which case you’ll need to re-flash the same ROM (without formatting data) to ensure both slots have post-ARB firmware.

You can read proper flashing instructions here.