There are some methods that I found checking if your email account is affected in any data breach.
- You can visit below websites, insert your emails, and verify which websites faced any data breach.
https://haveibeenpwned.com/
https://www.avast.com/hackcheck & https://www.f-secure.com/en/home/free-tools/identity-theft-checker (in this case you will receive an email report on your account)
https://monitor.firefox.com/ (in this case you will receive real time emails when data breach will occur on your accounts. PREREQUISITE be aware that firefox email account creation is necessary) - Alternatively, to have constantly your emails accounts monitored, you can install Avast Antivirus on your your mobile devices (there is a section where put your emails accounts to be monitored)
ANDROID
https://play.google.com/store/apps/details?id=com.avast.android.mobilesecurity
IOS/IPHONE/IPAD
https://www.avast.com/it-it/free-ios-security#pc