Blogger Cody Hosterman recently published a blog on the topic of booting from a SAN via NVMe-oF, which he believes is only currently supported via Fibre Channel. Check out his full article, which is full of great resources including a list of NVMe-oF capable HBAs.

Check it out here: https://www.codyhosterman.com/2021/02/whats-new-in-purity-6-1-esxi-nvme-of-fibre-channel-boot-from-san/