You will not find your phone in the list of block devices because your phone does not present itself as a block device. HarmonyOS is based on Android 10. As far as I know, Android 10 only offers the Media Transfer Protocol (MTP). When the phone is configured to offer mtp, you will see it in the output of `lsusb -v`:

```
Device Descriptor:
  iManufacturer           1 manufacturer
  iProduct                2 phone
  …
  Configuration Descriptor:
    iConfiguration          4 mtp_adb
    …
```

You can access the files with any mtp client. I prefer mounting with `gvfs-mtp`, but any of the clients listed in https://wiki.archlinux.org/title/Media_Transfer_Protocol will do.