I can hurl a bunch of Portuguese names at you (none of which are/can be unisex, sorry). Let's see, how about Lago (LAH-goo), which means lake? Or
Rio (REE-oo), river. Poça (POH-sa), puddle. Ironically, out of these three only poça is a feminine noun. Hmm, maybe Lagoa (luh-GO-uh) - small lake? Or Chuva (SHOO-vuh), rain. Or
Nova (NAW-vuh), meaning new.
Or you if you have a particular place/feature in mind, I can translate it for you?
By the way, this is an unnecessary tidbit of info, but Kona spelled with a c is a very heavy slang word in Portuguese.