M20 is much better! Things that M20 has that A20 doesn't have: ⭐️ Light Sensor ⭐️ Fingerprint Sensor ⭐️ Face Unlock What about A20: ⭐️ It's light

They are not that much different but m20 battery capacity is better

https://m.gsmarena.com/compare.php3?idPhone1=9640&idPhone2=9506

A20