Should legal professionals have more than one mentor? Should seasoned legal professionals have mentors?

Should legal professionals have more than one mentor?
You bet! And the more mentors the better!
Should seasoned legal professionals have mentors?
The answer is the same: you bet!
Law is a fascinating field, each practice area presents their own body of knowledge often found in statutes and case law. But there are conventions which tend to be passed on orally. If you happen to be in a workplace where there is a senior person involved, hurry and get as much mentoring before they retire!
For those who consider pupilage as part of practice, they will actively train juniors professionals.
For those who have lawyers who are to busy, then there are many continuing professional development resources internally and externally.
One that is noteworthy is volunteering, in Vancouver, there is Amici Curiae Friendship Society, volunteers get to network with legal professionals from different fields, each with varying tenure. Volunteers also get exposed to different areas of law. Curious? Check them out: https://www.legalformsbc.ca/legal-professionals.html.