Kia ora! I'm an #NZGreens member, and one of the co-convenors of the Green Geeks network for techie people.
As far as I know there are no Green MPs currently using Mastodon, but there are plenty of members. I’m currently working on a position paper on social media which will advocate for a presence here. It's a classic challenge for any progressive organisation though: do you spend your time on building the world you want to see or on engaging with people in the world as it is? The answer always needs to be a balance of both, but at the moment we need to reckon with the fact that the raw numbers of users are stacked against spending time on Mastodon. Especially during an election year, it's a hard case to make for a very busy media team.
I’ll be emphasising that Mastodon users are disproportionately going to be people who’d consider voting Green, and look for ways to get started. In the meantime, we can make sure members have a visible presence.