Connecting a USB hard drive to a openwrt router without a usb port

There is no solution, but you can develop it yourself... in several years. Or you can stop wasting your time and spend 10-20$ on router with usb.

Get yourself a raspberry pi 2/3 and connect the harddrive to it. Im running exactly 7 tapo cameras with ffmpeg creating 5 mins segment files from RTSP stream. Also install samba on the pi. Create a wireguard vpn on the router and you can access the samba drive with vlc app and remote view the files

Thanks everybody for the support and suggestions.

I will first try with an old TD-W8970 that I already have and, in case of problem, with a raspberry.