Which NTP time library works unified and offline for ESP32 and ESP8266?

Hi Folks,
I have spent now so much time trying to find a unified NTP time library that will work for ESP32 and ESP8266 altogether.

It should be able to run oflline after the initialisation with NTP, resynchronise periodically, and provide the ability to extract the time components like hour, minute, second.

I have made several failed attempts with
-the NTPtimeESP.h library of A-Spiess (does not run offline)
-the ESPDateTime.h library of mcxiaoke (cannot handle timezones on ESP8266)
-the default simpleTime from ESP (does not run on ESP82669)
-the Thingpulse library from D-Eichhorn (does not run on ESP32)

Could I get your experience on what runs well on both ESP devices?
Thank you.