You won't like the result. The water in the egg white moves about and crystallizes when it freezes, altering the structure, so that when the egg is thawed, the white is both watery and rubbery.

You can freeze the yolk, however, and, once thawed, crumble it on salads or use it for a garnish. But it won't have the smooth, almost paté-like texture one finds in a freshly hard-boiled egg.

In either case, freezing is not really the highest and best use of a hard-cooked egg.