You might be thinking of the option to allow a member to take charge of assigning mentors. That can be assigned in the Email and Contact Forms module. The member then has access to the membership list for assigning mentors and mentees, and also the relevant mentoring reports from the Membership Management module.
See the Mentoring Form section here:
support.toastmastersclubs.org/doc/item/email-and-contact-forms
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