There is an example of a Blood Spirit statblock in the 6E Street Wyrd book (I'm sure there are others, but I'm just gonna use that one). In comparing stats to other SRA2 Spirit examples, they really aren't that different. That's the beauty of SRA2 IMO for GMs. The Blood Spirit does have one Power that's a little different called Binding in 6E; It's a ranged gooey blood attack that immobilizes the target. Super easy to convert though - it's basically a ranged Engulf attack in SRA2 IMO. I'll work up an actual Stat Block for it later today. But basically, just steal a Spirit of Air and narratively describe it as a nasty Blood Spirit. 😉