Apparently, there are quite a few of these doujinjshi out there. Around 7 or 8(!). That's quite a long run. Considering I'm a fan of genderswap, and of Kyonko in particular, I'd like to get my hands on them and upload them here. The only problem is all the ones I can find are in Chinese. My Japanese skills may be limited, at best, but I'm sure we'd all prefer them in the native tongue rather than having them translated twice over.
In short, if anyone could help search for these, I'd appreciate it.