Plus, Argonians are really the lizzards we think of apparently they are warm blooded, so maybe they have the full works down there?
While I understand this was half a joke, this is really something to consider. Argonians are lizard-like in many ways, but they are not lizards per se. The line between male and female in real world lizards is really quite faded, as they do not have, ah, "traditional" genitalia. In contrast, Argonians at least appear to be quite human in their distinctions between male and female, and on top of this, it is apparently possible for Argonians to hold sixual intercourse with humans.
Long story short, do not assume too much about the beast races. All we know is that they are at least aesthetically similar to cats and lizards.
(( Ya didn't see Yoshi wearing no dungarees, just some boots and a harness, kinky! ))
WARNING: NERD TANGENT IMMINENT.
Yoshis are sixless. They do not require partners to reproduce but instead lay eggs after consuming extreme quantities of food stuffs.