As a general rule, you cannot block synthetics, only natural fibers. You can
block it, but after you wash and dry it, it'll just go back to the way it was before, but washing synthetics is sort of like blocking, it causes the stitches to bloom and open up. It's never like a true lace blocking, and lace requires stretching so you can actually see it. If the yarn you're using is like a light halo, then it won't really obscure the design, but if it's like a fun fur (
) than lace will look like any other knitting would in that yarn. But remember - lace should always be knit in a yarn that can be blocked (and I mean blocked, lace needs stretching to open up the pattern), and not in a fuzzy yarn, so you can actually see the pattern.