It would be of no use, except as a form of "false flag" psychological warfare. It may simply serve to antagonize Catholic beliefs, and possibly to set up/reinforce false ideas about transubstantiation / the sufficiency and efficacy of Christ's once-for-all sacrifice on the cross.
"Catholicism must be true, if the Satanists think so!"
Ditto!
Looking to Satanists for validation that their particular faith group is true?
Satanic rituals require consecrated hosts. Only they suffice. If the psychological aim which you suggest held water, it could be achieved just as easily with an unconsecrated host, or something approximating the appearance thereof, since who could tell the difference? There would be no need to go to the trouble of breaking into Churches or sneaking them out at Communion time.
This is more than just play-acting. There is a significant amount of anecdotal evidence that those deeply immersed in Satanism can actually pick out a consecrated host amidst unconsecrated duplicates. Which should come as no surprise to anyone who believes that (i) Satanists are serious (ii) some are endowed with supernatural powers and (iii) the consecrated host is actually what the Church has always claimed it to be.
They're worshiping Satan. Period. Asking for his Satanic benediction. For that, they require consecrated hosts. It's that simple.