That is up to Diarandor. I do not want to take time away from his works and it would be best for me to complete everything I can before asking for others to join in.
Hi Zefk! Do not worry, you are not taking my time away. We can coordinate our work if you want, for the sake of the Children of Solarus project. (We can talk better on the IRC Chats if it's ok for you.)
I am focused on the graphics of the hero, which includes animations for weapon attacks, and also the weapon inventory items (to have consistency with the weapon sprites of the hero attacks). I also made almost all the sounds (I can do the remaining ones one of these days). I plan to make the graphics for NPC's when I finish all of this.
So you can focus on free (or at least, zero-price) tilesets fitting with the ones in ALTTP, and also the musics, and with that all would be done. Maybe you can create/find NPC graphics that fit with the project, too.
As I usually recall, my graphics are not free as in freedom since they are
non-commercial (the licence is CC-BY-NC-SA 4.0), they are just zero-price. For people without commercial concerns that should be ok (if someone wants to use them for a commercial game, a deal with me could always be possible). For the Children of Solarus project that license is good enough too.
Anyway, if someday someone creates
free graphics for all the hero animations of nice quality (which is a huge work), then we could replace my art for the free one in the Children of Solarus project, which would be better for other people with commercial intentions. As far as I know, no-one is working on this (at least using a free licence), and it would be necessary to keep the size of the hero sprites (for compatibility) and make all the animations. Most of the internet free art for a hero is incomplete (most animations are missing), or does not fit with what is needed here.