namecrazy59's list "Unisex Names" of 3 great name ideas: Tiernan - Bryce!

Unisex Names

An old Irish surname cousin of Tierney that makes an unusual and appealing Irish gender switch.

Tiernan

An early and still quintessentially gender-neutral name, now supplanted by thousands of fresher options. Hasn't been recorded as a given name since 1991.
 
Pat was the name of a gardener in Alice's Adventures in Wonderland, Jake's daughter-in-law in Adventure Time, and a recurring androgynous character on Saturday Night Live.

Bryce is the preferred spelling over Brice for both genders, with nearly 70 girls named Bryce in one recent year vs. only five called Brice.  But note that there were over 3000 boys named Bryce and 240 named Brice, making this a predominantly male name.  Actress Bryce Dallas Howard, daughter of director Ron, is the most notable female bearer of this name.