We began offering volunteers the option to include pronouns on their name badges this year, and it's been very positive I think. Some volunteers (especially many of my seniors) opted out and it was no big deal, but many others thanked me for the opportunity to start doing that. Staff have had pronouns on our nametags and email signatures for a few years, so I think that helped introduce the idea to some who might not otherwise have been as familiar with the practice.
We use the nametag.com program to print paper inserts for plastic pin-on badges, so it's easy for me to make replacements. Our nametags aren't huge and also include first name and "volunteer since (year)", so they don't look empty without a pronoun line either.