Any way to batch change block types in a blueprint?

Hello all. I am working on making a copy of the Abaddon (an Eve Online battleship), and I have made a decent size rough draft so far, but I messed up and made it from combat steel in creative mode, and I realize it is going to take 25-30k Sathium.

I want this ship to be possible in survival mode, and with those numbers I do not see it being worth making.

I was wondering if there was a way to batch change block types (from combat steel to hardened steel) either in creative mode or in the...

Any way to batch change block types in a blueprint?