Can I play in different region?

[Vanillataur-nethergarde-keep]

Yes you can - if you want to pay. You can play Retail with an EU account, but not Classic.
I used this for my How2 when I made a USaccount:

Play US servers from EU account

This question has probably been asked before but I can’t seem to find a sure answer that perfectly applies to what I need to know. I have an EU battle net account and I have always played WoW on EU servers. Now I would like to play with my Canadian friends. Is there any way for me to do this with my current account or will I need to create a new one where I say that I live in Canada? (I did try this but got the error that my email address is already connected to an account.) Does this mean tha…