When i switched to a new android phone I noticed that logging in my usual opera account was possible, but it took weeks until opera app requested my passphrase in order to sync my bookmarks and everything else, like you do when you log in to your account. I am happy that it worked in the end, since I was researching how I can get my passwords and bookmarks to my new device. Hope that helps. Hope that Opera will amend this, like you get asked your passphrase after logging in, in order to sync everything straight away.