Questions & Answers about Eu não esperava isso.
Yes. In Brazilian Portuguese, subject pronouns are often optional, so Não esperava isso is a very natural sentence.
Eu is included for one of these reasons:
- to add emphasis
- to make the subject extra clear
- to contrast with someone else, as in Eu não esperava isso, mas ela sim
So both are correct:
- Eu não esperava isso
- Não esperava isso