I don't blame you- it's quite a tedious process without Collada Tool, which unfortunately didn't work for me either.
To do this, you'll need five tools:
UnPSA Toolkit -
http://www.david-najar.com/downloads/DN UnPSA Toolkit v0.38b.zip
To merge all your PSA files into one for use with ActorX
Brawlbox -
https://github.com/libertyernie/brawltools/releases/download/v0.78_h1/BrawlBox.v0.78.Hotfix.1.exe
To export all your animations in CHR0 format
BRRES Viewer -
https://tcrf.net/images/4/41/BRRES_Viewer_1.3.1.zip
To export your model to PSK along with your animations in PSA
ActorX Plugin -
http://www.gildor.org/down/41/actorx/ActorXImporter.zip
Use with 3DS Max to export the animations as FBX files. Move these files into the Scripts folder in the 3DS Max folder located
3DS Max -
https://www.autodesk.com/education/free-software/3ds-max
Software to use ActorX with. You'll have to make an account to be able to download it, and the filesize is 6-7 GB, so be warned.
You can't use the model you exported already for these animations, as it will not work properly. Only the one exported in this method works.
To begin, look into the fighter folder of your Brawl filesystem. Then, choose the folder of a character you want to get into Unity, and put that folder in a location you'll be using for the rest of this process. Then, open Brawlbox. With it, open one of the character model .pac files, explore it until you reach the BRRES file containing the model data, and export the entire BRRES file. Next, open the motionetc(animation file) in BrawlBox until you reach the BRRES file containing the animation data, and export the entire BRRES file. Next, open BRRES Viewer, and open both BRRES files you exported. Load up the model in BRRES Viewer by finding it in the model folder and clicking it, and export it as a PSK file in the model tab. Here comes the long part. Next, while the model is still loaded, load an animation in the animation folder, then when it begins playing, go into the animation tab, and export the animation as a PSA. You have to do this for every single animation you want to export, and if you decide to do it, export them all into a single folder for later. When you finish exporting all the animations you want, along with the character model, open UnPSA Toolkit, and press the Add Animations button. Go to the folder where you put all your PSA animations, and select all of them, then add them. Then click on the first one in the list that appeared, and press on the "Add" button at the middle right corner. Do this for each animation in the list, and make sure you clicked on them all and added them all. Then, press on the "Save PSA" button in the bottom right corner, and save the psa file. Next, open 3DS Max, and click on the Scripting tab, and then on Run Script. Go to the "actorx" script you put in the 3dsmax script folder, and run it. Then, click on load psk, and load the psk file of your character. next scroll until you see the load psa option, and load your psa file you created with unPSA toolkit. load it, and the scroll for the batch export option. click it, and then scroll all the way down, and click the export option. it should take some time depending on how many animations you loaded in the psa, but it will finish. Once that's done, there should be a folder labeled FBX wherever you had your psa at. open it, and there should be a folder named the same as the psa. Congratulations! That's the folder containing all the animations you exported in the form of fbx files. Take that folder into Unity, and that should import. Next, we have to create a prefab of our character. To do that, drag an fbx file into the heigharchy, rename the prefab to your character, then drag it into the project window, and now you have a prefab that works with the animations. That's it.
