On a new install of P4 and Android mode v 4.6, I get this error:
processing.mode.android.AndroidSDK$BadSDKException: Cannot find avdmanager in C:\Users\****\Documents\Processing\android\sdk\cmdline-tools\latest\bin at processing.mode.android.AndroidSDK.findCliTool(AndroidSDK.java:410) at processing.mode.android.AndroidSDK.<init>(AndroidSDK.java:167) at processing.mode.android.AndroidSDK.locate(AndroidSDK.java:537) at processing.mode.android.AndroidMode.checkSDK(AndroidMode.java:168) at processing.mode.android.AndroidEditor.<init>(AndroidEditor.java:86) at processing.mode.android.AndroidMode.createEditor(AndroidMode.java:83) at processing.app.Base.handleOpenInternal(Base.java:1613) at processing.app.Base.handleOpenUntitled(Base.java:1601) at processing.app.Base.handleNew(Base.java:1129) at processing.app.Base.changeMode(Base.java:1035) at processing.app.ui.Editor.lambda$rebuildModePopup$1(Editor.java:467) at java.desktop/javax.swing.AbstractButton.fireActionPerformed(AbstractButton.java:1972) at java.desktop/javax.swing.AbstractButton$Handler.actionPerformed(AbstractButton.java:2313) at java.desktop/javax.swing.DefaultButtonModel.fireActionPerformed(DefaultButtonModel.java:405) at java.desktop/javax.swing.JToggleButton$ToggleButtonModel.setPressed(JToggleButton.java:411) at java.desktop/javax.swing.AbstractButton.doClick(AbstractButton.java:374) at java.desktop/javax.swing.plaf.basic.BasicMenuItemUI.doClick(BasicMenuItemUI.java:1028) at java.desktop/javax.swing.plaf.basic.BasicMenuItemUI$Handler.mouseReleased(BasicMenuItemUI.java:1072) at java.desktop/java.awt.Component.processMouseEvent(Component.java:6626) at java.desktop/javax.swing.JComponent.processMouseEvent(JComponent.java:3389) at java.desktop/java.awt.Component.processEvent(Component.java:6391) at java.desktop/java.awt.Container.processEvent(Container.java:2266) at java.desktop/java.awt.Component.dispatchEventImpl(Component.java:5001) at java.desktop/java.awt.Container.dispatchEventImpl(Container.java:2324) at java.desktop/java.awt.Component.dispatchEvent(Component.java:4833) at java.desktop/java.awt.LightweightDispatcher.retargetMouseEvent(Container.java:4948) at java.desktop/java.awt.LightweightDispatcher.processMouseEvent(Container.java:4575) at java.desktop/java.awt.LightweightDispatcher.dispatchEvent(Container.java:4516) at java.desktop/java.awt.Container.dispatchEventImpl(Container.java:2310) at java.desktop/java.awt.Window.dispatchEventImpl(Window.java:2780) at java.desktop/java.awt.Component.dispatchEvent(Component.java:4833) at java.desktop/java.awt.EventQueue.dispatchEventImpl(EventQueue.java:775) at java.desktop/java.awt.EventQueue$4.run(EventQueue.java:720) at java.desktop/java.awt.EventQueue$4.run(EventQueue.java:714) at java.base/java.security.AccessController.doPrivileged(AccessController.java:399) at java.base/java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(ProtectionDomain.java:86) at java.base/java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(ProtectionDomain.java:97) at java.desktop/java.awt.EventQueue$5.run(EventQueue.java:747) at java.desktop/java.awt.EventQueue$5.run(EventQueue.java:745) at java.base/java.security.AccessController.doPrivileged(AccessController.java:399) at java.base/java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(ProtectionDomain.java:86) at java.desktop/java.awt.EventQueue.dispatchEvent(EventQueue.java:744) at java.desktop/java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:203) at java.desktop/java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:124) at java.desktop/java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:113) at java.desktop/java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:109) at java.desktop/java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:101) at java.desktop/java.awt.EventDispatchThread.run(EventDispatchThread.java:90)
It appears that this line:

will always fail when looking for the 'avdmanager' and 'sdkmanager' because these are .bat files not .exe. The only .exe in your toolchain requirement is 'adb'.

Currently, there is no way to install Android mode v 4.6 on WIndows.

Version 4.5.1 does work and it appears that you do check for both .bat and .exe files in the findCliTool() method.