You best bet is to get a USB 2.0 Hub with a Terminus chipset such as FE 1.1 or NEC chipset. The most common chipset is by VIA (probably used by your UGreen hub) but they are not usually Android compatible. So perhaps only 35% of the USB Hubs on the market will work. You can determine the chipset by running a freeware called ChipGenius but be careful that some versions of the freeware may have a malware signature.
An example of a common USB 2.0 Hub that can be powered which has a Terminus chipset is the SMAYS 'Ethernet Adapter Replacement for TV Stick 4K ... Micro USB OTG Cable HUB with Power'. This is not an ad for them because the ethernet that come with it (chipset RTL8152) is NOT compatible with the TS4K but the USB Hub is compatible. Apparently the FireTV and Chromcast have built in support for that RTL8152 but the Tivo Stream 4k does not.
OTG cables allow you to connect your usb devices to the back of the ps classic where you don't have to worry about power requirements. They are like usb passthrough cables. One of the key things about using project eris/bleemsync is that they support OTG. They're very cheap and a cleaner solution than using powered USB hubs.
This is a recommended one.
I've only controlled one FireTV (well, two on the same job), and I used a FLIRC with this adapter which allowed connecting additional USB devices with the power supply (and LAN). I found it described somewhere searching Google. The USB port on the official Amazon LAN adapter only accepts power, you can't hookup a hub to it for other USB devices.