Same Problem… (UE 4.26)
Solved it with this steps:
Download JDK v.8 and set it in UE Program Settings/ Platforms/ Android SDK - Location of JAVA - solved some errors but not all!
I notice that the UE auto NDK download has instaled NDK versión 21.1.6352462 - and in the UE docs (Updates to required setup for Android NDK 21 in Unreal Engine 4.25 - Unreal Engine) recoment 21.0.6113669
So i changed the NDK to 21.0.6113669 using already installed the Android Studio 3.5.3:
Open Android Studio
Configure
SDK Manager
SDK Tools
show Package Deteils
Install NDK 21.0.6113669
Open UE project:
Change the NDK versionfolder in your project UE Program Settings/ Platforms/ Android SDK - Locación of NDK 21.0.6113669
this solved the problem for me.