Most of them I used the debug frame advance in dolphin and took a screen then advanced (I also spent some time trying to make the camera as consistent as possible). I couldn't have done it without summer break and a lot of patience (though not all of it was done within the summer for sure. Then I used GIMP to edit the frames and export them as gifs. I put in a lot of hours to make that happen, but I did learn a lot about short-keys to use for renaming files, organization skills, and eventually, too little too late, I learned scripting and made a script to alternate taking frames and advancing which I could enter x frames or end the frames by holding a key and just delete the last ones if it took too much.
If you automate the screenshot taking process, you could actually get through a character in only a few hours I think. I wouldn't bother with the hacking to go through the animations, just input the commands manually on the first frame or you could make a script to even input the commands, move files, rename, etc. It's VERY time consuming if you do it by hand, but if you have time and patience it can be done. I would not recommend it, however. If you can script, you can cut the time down tremendously.
Also, you need to multiply the animations by 2, because it will look different face left or right... probably. I would do just Fox first (for example) and try analyzing Fox dittos and get that working, if that works, begin going down the list. the high tiers. I wouldn't bother going further down the list than young link because they are almost never used. If I were you I would MAKE SURE that the analysis is going to work before collecting all the data and discovering you can't do it.