Definitely necessary to have EE profile. In the forms and the website, they tell you to create an EE profile if you haven't done so already.
"All nominees of the NBPNP EELMS must have a profile in the CIC Express Entry pool to receive a NBPNP electronic nomination. "
"*All individuals who receive an invitation to submit an application must first have created a profile in the federal Express Entry system.
The NBPNP needs the Express Entry Profile Number and the Job Seeker Validation Code for all applications.
*Please ensure that your federal Express Entry profile is valid and active for at least 6 months from the date you submit your application to the NBPNP."
But I have found in FAQ of NB-
17. What is the process for prospects who want to use both the Provincial Nominee Program and the Federal Express Entry system?
There are two ways to do this. A person can:
a. apply to the NBPNP first, receive a nomination, and then fill out an Express Entry profile; or
b. fill out the federal Express Entry profile prior to submitting an EOI to the NBPNP. When the candidate receives a nomination certificate, they will update their Express Entry profile.
In either case, once a person updates their Express Entry profile to show they have a nomination certificate, they increase their likelihood of being invited to apply to permanent residency by CIC.