I wish this site would just list all the matches. If you keep clicking the button, it'll cycle (randomly!) through other substitutions.

Sparkling was also immaculate. "Demanding" was also arduous, grueling, backbreaking, and formidable.

Surely one of those would work for replacing "very hard" in a sentence? If not, then use your own imagination. "Complicated", "tedious", "rock hard", etc.

Sometimes you have no choice but to throw a "very" in there. But if you're the type to lean on that word, then it's worthwhile to explore alternatives to avoid boring writing.