Depends on your goal. If you want a tropical reef tank, and are just trying to avoid spending money on hermits and anemones, the high temperatures will probably cause them to die fairly quickly. Their biochemistry is geared to low temps, they won't do well in warm water.
On the other hand, if you want to outfit a tank for native species, go for it. You will definitely need a chiller, which will be expensive. Plus, I don't know how much information there is on keeping a lot of those guys. Almost all the hobbyist literature is written about tropical species. You would be right on the cutting edge.
The only other issue I can think of is that blue legs are relatively peaceful creatures, while some hermits, especially large ones, can be really obnoxious.