After extracting (Windows, Mac) your Windows Phone's WhatsApp archive (messages.db) you need to move it to your new Android device. You need to put it inside the (auto-created) WazzapMigrator folder, like this.

If you can't see the auto-created WazzapMigrator folder just restart your phone.

WINDOWS

wazzapmigrator folder structure - windows

 

MAC

wazzapmigrator folder structure 

Please note that WazzapMigrator will search it in other folders too, like Downloads folder.

Folders where WazzapMigrator will search for messages.db

Or you can select it manually:

select chatstorage manually