Have a client with overdeveloped calves. I would not want to advise any weight training. Any other suggestions?

There is really nothing you or she can do about this. Genetics cannot be changed. You can have her do all types of exercises without focusing on the calves alone (for ex. no calf raises). Walking alone exercises the calf muscle, so even if you advise her not to do any weight training for her calves, they will still get worked out indirectly.