hermits when breeding approach each other and the male "tickles" the females legs and then puts his smaller legs inside her shell,
they then both hop out of the shell and put their ventral surfaces together for a few seconds then get back into their shells quickly.
hermits can also fight with each other over shells this is a more violent affair with tussling back and forth and shells being tipped over
i hope they are breeding, good luck
some species disperse eggs into the water, and some keep young in their shell