I've moved some domains to Cloudflare Registrar not knowing this limitation. I asked them about it and the support person said they are targeting Q1 2019 for this feature. Now that we're approaching that date I'm not sure they'll hit that.

I've also had a billing issue with Cloudflare Registrar. I transferred two domains and paid the renewal fee, and two months later was charged for the same domains again. They've since issued a refund after I raised a support ticket (still waiting on that to hit my card), but the fact that it happened at all is worrying to me.

Granted I was in early access so I expected some things not to be polished yet, but these are pretty critical areas to get right as a registrar. And since my billing issue happened just last week I doubt that issue has been fixed with the general release.

So I'm going to hold off on transferring more domains until it matures, or just stick with Gandi.