ipad os lighting to external harddrive

Trying to get my 2017 iPad Pro that is running iPad OS, and my iPhone XR, running 13.1, to read/write to external hard drives, memory sticks, and SDHC Cards by lighting port adapter. So far:

1 - PNY ATTACHÉ 4GB USB Drive works via a dongle. (Do we still call them "dongles" 😅.)

2 - Of the exact same drives throw the error "requires too much power". 🤔

1 - Cruzer Micro USB Drive throws the error.

2 - No Name USB Drives work fine.

1 - SanDisk SDHC Card works fine.

4 - External Harddives throw the error, even when self powered, or powered by a three way cable/power supply. 🙈☹️

1 - Logitech M310 USB Mouse.........WORKS! 😁🎉🎉🎉🎉🎉🎉🎉

Absolutely totally stumped on the error messages with the thumb drives, and ESPECIALLY the hard drives. ☹️☹️

Any ideas?