If you are using Fat32 as your microSD's formatting system (which you SHOULD do to avoid your stuff corrupting!!),
then you'll have to recombine the file from 4 subfolders into one complete file.
Refer to here for a more thorough explanation, as this isn't the point of this guide: https://gamebanana.com/tuts/12827
grab foobar2000 and the VGM stream component for it:
open up foobar2000, click File in the top-left, go to Components in the window that comes up, and select install.
Find the component you just downloaded and install it.
You can play (most) nus3audios in foobar2000 now, so you can listen to music, voices, sounds, and audio in general from Ultimate.
You can also rip the audio from here.
Simply open up a nus3audio, select the clips you want to rip like you would files within the window (i.e. CTRL+A to select everything),
move down to Convert in the dropdown that appears, and choose default, then pick a destination folder.
If ripping from a file with more than one sound in it, you will see some numbers in front of the clip's name. These are *VERY NEARLY* the sound ids, as they're all individually one number too high. Rename all of these to be one number down,and remove the rest of the name,and you'll have the ids that you need.
For example, vc_captain_c00#1 would become 0 (and I mean just the number 0, don't include anything else in the filename.
Once this whole process is done, you should have a folder full of clips named just by number (i.e. 0-46). Replace these as you see fit.
Here's a general list of what corresponds to what for voice clips:
Attack01 through Attack04- used for aerials and tilt attacks
Attack05 through Attack07-used for Smash Attacks
Attack08 and above (if present)- used for attacks of course, but these don't follow a general rule
cliffcatch- used for grabbing the ledge
damage_twinkle- used for blasting off again, I mean star KOs.
damage01 and damage02 (also damage 03 and damage03_02 for Bayonetta)- used for being knocked back at low percentages. Try to keep these short and easy to listen to, as they repeat CONSTANTLY at times. Also, Mii Swordfighter flat out doesn't use these until insane percents for some reason.
damagefly01 and damagefly02- used for big knockback at higher percents.
furafura- used for shieldbreak/being stunned.
furasleep- used for sleeping.
wakeup- used for waking up from sleep
heavyget- used for picking up heavy items
jump01 and jump02- jumps
missfoot01 and missfoot02- death clips, the first one is commonly used, while the second has a random chance to play instead.
passive- used for teching being knocked into a wall/floor/ceiling.
swimup- used when surfacing in swimmable water.
win01 through win03- used for thw win animations, the Left dpad, Up, and Right dpad animations respectively I believe.
knockout- used for running out of health in stamina mode.
special_ - used for specials, H being up, N being neutral, S being side, and L being down.
final01 and up- used for a character's final smash.
smash_- ALSO used for Smash attacks typically, if present.
001 through ???-these can be used for ANYTHING. this is generally whatever the Smash dev team didn't care enough to label.
note that these are GENERAL rules, and there WILL BE exceptions. Bowser in particular is especially weird with how he uses his.
once you've replaced the clips to your liking AND properly renamed them to their number ids (which are one down from what foobar tells you they are), make a .zip with just the clips inside of it.
(as in if you open it up via double click, there is no folder inside it, just the clips.)
once you have that zip made, head here:
you'll upload the zip you just made and pick a sample rate, which is important if you want to keep filesize low enough to use with Ultimate Mod Manager,
although using UMM for voices in general (and putting up with filesize limits for voices in general) is no longer an issue if you are using ARCropolis. That won't be explained here.
Anyways, once you're ready, hit convert, and you'll get a .zip from the site named "out".
After that, head here:
upload the ripped nus3audio that you got the unmodified clips out of in the first place, (although edited ones also work), and choose the "out" .zip you just downloaded.
Hit convert, and the site will spit back out a new nus3audio, with your edited sounds from the "out" zip file you just gave it.