The app can start when I remove all resolved .aar and .jar in Plugins/Android except the googlemobileads-unity.aar. If I resolve everything with the Android Resolver the app crashes on startup. AppID is set properly. Older mobile ads unitypackages have the same result. It worked before in Unity 2019.
06-20 02:34:12.971 1275 1334 I HwAudioServiceEx: ComponentInfo : className = com.unity3d.player.UnityPlayerActivity, flag=showStartingWindow, isHomeActivity=, isTop=false
06-20 02:34:12.986 1275 1299 I WindowManager: Check opening app=AppWindowToken{dc7a3d5 token=Token{a8cd08c ActivityRecord{dffdbde u0 com.GermapurApps.MinerGunBuilder/com.unity3d.player.UnityPlayerActivity t835}}}: allDrawn=false startingDisplayed=true startingMoved=false isRelaunching()=false startingWindow=Window{fcaa524 u0 Splash Screen com.GermapurApps.MinerGunBuilder}
06-20 02:34:12.986 1275 1299 D HwWindowManagerServiceEx: is app exit to launcher info: transit = 12, app = AppWindowToken{75386ca token=Token{1214235 ActivityRecord{1bafbc3 u0 com.ss.squarehome2/.MainActivity t665}}}, window = Window{28525dc u0 com.ss.squarehome2/com.ss.squarehome2.MainActivity}, mClosingApps = {AppWindowToken{75386ca token=Token{1214235 ActivityRecord{1bafbc3 u0 com.ss.squarehome2/.MainActivity t665}}}}, topOpeningApp = AppWindowToken{dc7a3d5 token=Token{a8cd08c ActivityRecord{dffdbde u0 com.GermapurApps.MinerGunBuilder/com.unity3d.player.UnityPlayerActivity t835}}}, mExitIconBitmap = null, mExitIconHeight = 0, mExitIconWidth = 0
06-20 02:34:12.987 1275 1299 D HwWindowManagerServiceEx: is app exit to launcher info: transit = 12, app = AppWindowToken{dc7a3d5 token=Token{a8cd08c ActivityRecord{dffdbde u0 com.GermapurApps.MinerGunBuilder/com.unity3d.player.UnityPlayerActivity t835}}}, window = null, mClosingApps = {AppWindowToken{75386ca token=Token{1214235 ActivityRecord{1bafbc3 u0 com.ss.squarehome2/.MainActivity t665}}}}, topOpeningApp = AppWindowToken{dc7a3d5 token=Token{a8cd08c ActivityRecord{dffdbde u0 com.GermapurApps.MinerGunBuilder/com.unity3d.player.UnityPlayerActivity t835}}}, mExitIconBitmap = null, mExitIconHeight = 0, mExitIconWidth = 0
06-20 02:34:12.997 1275 1405 I ActivityManager: Start proc 14462:com.GermapurApps.MinerGunBuilder/u0a224 for activity {com.GermapurApps.MinerGunBuilder/com.unity3d.player.UnityPlayerActivity}
06-20 02:34:13.037 1275 16066 W ActivityTaskManager: finishTopCrashedActivityLocked Force finishing activity com.GermapurApps.MinerGunBuilder/com.unity3d.player.UnityPlayerActivity
06-20 02:34:13.075 1275 15343 V WindowManager: removeAppToken: AppWindowToken{dc7a3d5 token=Token{a8cd08c ActivityRecord{dffdbde u0 com.GermapurApps.MinerGunBuilder/com.unity3d.player.UnityPlayerActivity t835}}} delayed=true Callers=com.android.server.wm.DisplayContent.removeAppToken:1239 com.android.server.wm.ActivityRecord.removeWindowContainer:1332 com.android.server.wm.ActivityStack.removeActivityFromHistoryLocked:5115 com.android.server.wm.ActivityStack.removeHistoryRecordsForAppLocked:5534
06-20 02:34:13.075 1275 15343 V WindowManager: removeAppToken make exiting: AppWindowToken{dc7a3d5 token=Token{a8cd08c ActivityRecord{dffdbde u0 com.GermapurApps.MinerGunBuilder/com.unity3d.player.UnityPlayerActivity t835}}}
06-20 02:34:13.076 1275 16066 E InputDispatcher: Window handle Letterbox_top_AppWindowToken{dc7a3d5 token=Token{a8cd08c ActivityRecord{dffdbde u0 com.GermapurApps.MinerGunBuilder/com.unity3d.player.UnityPlayerActivity t835}}} has no registered input channel
06-20 02:34:13.111 940 1153 I Screem : <LOGMGR> <CreateNewActivityStartTask> [FLOW ERR, app=com.GermapurApps.MinerGunBuilder/com.unity3d.player.UnityPlayerActivity is starting, run new app=com.ss.squarehome2/ time=66020793]
06-20 02:34:13.111 940 1153 I Screem : <LOGMGR> <CountFlowErrBigData> [task=com.GermapurApps.MinerGunBuilder/com.unity3d.player.UnityPlayerActivity start=119, but no end.]
06-20 02:34:13.113 1275 1299 D HwWindowManagerServiceEx: is app exit to launcher info: transit = 26, app = AppWindowToken{dc7a3d5 token=Token{a8cd08c ActivityRecord{dffdbde u0 com.GermapurApps.MinerGunBuilder/com.unity3d.player.UnityPlayerActivity t835}}} mIsExiting=, window = null, mClosingApps = {AppWindowToken{dc7a3d5 token=Token{a8cd08c ActivityRecord{dffdbde u0 com.GermapurApps.MinerGunBuilder/com.unity3d.player.UnityPlayerActivity t835}}} mIsExiting=}, topOpeningApp = AppWindowToken{75386ca token=Token{1214235 ActivityRecord{1bafbc3 u0 com.ss.squarehome2/.MainActivity t665}}}, mExitIconBitmap = null, mExitIconHeight = 0, mExitIconWidth = 0
06-20 02:34:13.113 1275 1299 D HwWindowManagerServiceEx: is app exit to launcher info: transit = 26, app = AppWindowToken{75386ca token=Token{1214235 ActivityRecord{1bafbc3 u0 com.ss.squarehome2/.MainActivity t665}}}, window = Window{28525dc u0 com.ss.squarehome2/com.ss.squarehome2.MainActivity}, mClosingApps = {AppWindowToken{dc7a3d5 token=Token{a8cd08c ActivityRecord{dffdbde u0 com.GermapurApps.MinerGunBuilder/com.unity3d.player.UnityPlayerActivity t835}}} mIsExiting=}, topOpeningApp = AppWindowToken{75386ca token=Token{1214235 ActivityRecord{1bafbc3 u0 com.ss.squarehome2/.MainActivity t665}}}, mExitIconBitmap = null, mExitIconHeight = 0, mExitIconWidth = 0
06-20 02:34:13.113 1275 1299 W WindowManager: Failed to take screenshot. No visible windows for {taskId=835 appTokens=[AppWindowToken{dc7a3d5 token=Token{a8cd08c ActivityRecord{dffdbde u0 com.GermapurApps.MinerGunBuilder/com.unity3d.player.UnityPlayerActivity t835}}} mIsExiting=] mdr=true}
06-20 02:34:13.208 1275 1299 I WindowManager: Removing Window{fcaa524 u0 Splash Screen com.GermapurApps.MinerGunBuilder} from AppWindowToken{dc7a3d5 token=Token{a8cd08c ActivityRecord{dffdbde u0 com.GermapurApps.MinerGunBuilder/com.unity3d.player.UnityPlayerActivity t835}}} mIsExiting=
06-20 02:34:13.209 1275 1299 W WindowManager: Failed to take screenshot. No visible windows for {taskId=835 appTokens=[AppWindowToken{dc7a3d5 token=Token{a8cd08c ActivityRecord{dffdbde u0 com.GermapurApps.MinerGunBuilder/com.unity3d.player.UnityPlayerActivity t835}}} mIsExiting=] mdr=false}
06-20 02:34:13.209 1275 1299 V WindowManager: removeAppToken: AppWindowToken{dc7a3d5 token=Token{a8cd08c ActivityRecord{dffdbde u0 com.GermapurApps.MinerGunBuilder/com.unity3d.player.UnityPlayerActivity t835}}} mIsExiting= delayed=false Callers=com.android.server.wm.AppWindowToken.removeImmediately:994 com.android.server.wm.WindowContainer.removeImmediately:355 com.android.server.wm.Task.removeImmediately:215 com.android.server.wm.WindowContainer.removeImmediately:355
06-20 02:34:13.538 1275 1298 W ActivityTaskManager: Activity top resumed state loss timeout for ActivityRecord{dffdbde u0 com.GermapurApps.MinerGunBuilder/com.unity3d.player.UnityPlayerActivity t-1 f}
Currently the only simple and reliable workaround to show ads in my app is to use Unity ads which work flawless :/