Please do not rely on speedtest-cli, there are versions that shows wrong speed, see: https://dietpi.com/forum/t/rasberry-pi-on-dietpi-slow-network-speeds/3552/1
v6.26 did not contain some changes for the WiFi Hotspot. Note that not all WiFi dongles support AP mode, or they vary in performance/quality for that. To be sure it is an OS/config related issue, try to use exactly the same dongle that works well on Odroid, on RPi as well.
And please check dmesg and journalctl if there are any errors reported, the first kernel/driver related, the second command additionally can show software related messages-