You can say it nicely, but directly, "I completely understand why you may be telling people to knock this wall out, but I have seen some perplexed reactions. Would it be okay to tell people that, only if they inquire about making the kitchen bigger?"
If the potential buyer is bringing up the subject, then I'm sure your agent is just trying to let them know that there are options. The only thing I wish to add is that she must be sure that this is something that can be done. There could be issues preventing the knock out of this wall such as plumbing, electric or the fact that it may be a supporting wall.
Broker Associate, Paragon Real Estate Group CA DRE 01844627
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