If your router's USB port is needed just for external disk storage, then there is a great alternative on OpenWrt:
- install rclone + Samba4 (see configuration).
With this setup, you can mount your Microsoft OneDrive (or Google Drive) as a disk on the AX3000T router and share it over your local network like a NAS.
A practical example: shared network folder for scanned documents, or just storage for documents, etc.
In many cases, this can be an even better (cheaper) solution than using a regular USB flash drive.