I have a pattern that says to block with steam at the end since I am using stockinette. However, I used a different yarn - one that is 98% wool and 2% metal. The material is hand washable if that helps? Any advice on which blocking route to go?

I’d be nervous about steam on metal…I would probably suggest soaking, squeezing out gently but thoroughly, and then laying flat. If it’s OK to hand wash, then that shouldn’t cause a problem. I usually use my ironing board when I lay it out, since I can stick pins in the cover pad, and there are vent holes in the bottom of the metal board.