This list is very cool, efforts such as this is what makes this community awesome.
Question though. I noticed that you linked to the Japanese site tkool.jp which I
think is Kadokawa's main site? Well regardless, there are some additional material released there, most interestingly
this pack which looks like a celebration release for reaching 1.000.000 sales for the engine(?). It contains lots of sprites for many of the SF-RTP battler. Really, really nice stuff.
Now, I'll assume it's released by Kadokawa and that it's free to use (even for commercial games), as long as you own and use it in MV of course. But that's only an assumption based on the belief that the site and the resources in question belongs to, and have been release by Kadokawa respectively. As well as my (not perfect) translation of this statement on that download page:
■『RPGツクールMV』及び他ツクールシリーズ以外への転用は禁止いたします。
■本素材は、ユーザー登録をすることなく、ユーザーが任意で加工・改変するほか、加工・改変した本素材を無償で配布することが可能です。
ただし、『RPGツクールMV』で本素材を使用のうえ制作したゲームを配信する場合には、『RPGツクールMV』のユーザー登録が必要です。
■加工・改変した本素材の販売および本素材そのままを二次配布することは禁止いたします。
However, I can't go on an assumption alone when fact is that I can't read at a native level - which means I can't be sure. Also, as far as I do understand what's written, it doesn't seem to specifically say anything about what additional credits (if any?) that would be required. When it comes to legal stuff, the devil is always in the details, and I'm also unsure about the details of distribution mentioned. Is it fine to use and distribute (and sell as part of a game)? It doesn't seem to say anything about encryption though so is that maybe not needed? So many questions.
I want to be really, really sure since I might be tempted at using some of those sprites for a game that I might end up selling. Which would mean re-distributing them as part of a commercial product.