bypass "one-time password"

The only way to bypass it is to set-up a security key: http://www.swtor.com/info/security-key

You don't need the official app by the way, any authenticator app is compatible, like Google Authenticator or WinAuth. In the end, you have to enter some kind of code, and decide what is easier for you: checking your e-mails or your app. But you cannot turn the authentification off because it ensures that your account is more secure and cannot get hacked.

If you lost access to your e-mail account, the only way to gain access is to call them. You then have to answer the security questions you set up and can change the e-mail address. Phone numbers can be found at https://help.ea.com/en/article/swtor-support/ and you can call via Skype if international calls are too expensive for you.

Once you get back access to your account, you can decide if you want to stick with the one-time passwords on your new account, or add a security key. You can add security key by logging in to your account on swtor.com.