There are some more UPS especially for small electronics:
ebay.com/itm/Mini-UPS-Uninterruptable-Power-Supply-System-with-POE-Current-Transfer-Function/183952535867
ebay.com/itm/Mini-UPS-Uninterrupted-Power-Supply-7800mah-12V-2A-USB-5V-1A-Output-GM312/383191878917
ebay.com/itm/1575192-Vultech-UPS30PW-DC-Bianco-Mini-UPS-30-Watt-Gruppo-di-Continuita-Portatil/401874780975
ebay.com/itm/12V-USV-Mini-USV-unterbrechungsfreie-DC-Stromversorgung-12-V-22-W-2000-mAh/122971057294
Powerbanks with pass-through charging to use them as UPS:
Blitzwolf QC3 power bank 10000mAh BW-P3, fixed version
Blitzwolf QC3 power bank 15600mAh BW-P5
Miller ML202 V4
Ravpower Turbo+ RP-PB043 (20100mAh)
Soshine E4S
Thrunite C2 power bank and charger
Tomo Power bank M2
Tomo Power bank M4
And if you’d check he forum before, you’d find at first sight the following thread:
To get 12V out of USB, just use an QC or PD power source and add an USB QC trigger.