I had read an article that Phoenix was going to support Bolt 12 but that was over a year ago and it still doesn't. So far CLN supports it experimentally and as you know eclair can supposedly pay an offer and create one with a plugin. I updated to 0.10.0 and also have a CLN node with the experimental turned on. I haven't been able to successfully pay an offer yet between those two nodes.
It's still very unused and new.