I feel so embarrassed asking this, but this is my first time making cc for sims 3 and I'm honestly stuck.

I converted over some Eevee ears from Pokemon Scarlet and Violet, was planning to make some ears for use with the UNIFUR mod or to just use on Sims in general. Everything else has gone great, it's just for whatever reason when I add the mask to make it recolorable, it only works on the outer part of the ears? The inside remains the same color no matter what I do.

I don't really want to upload this without the ability for people to use create-a-style on it, does anyone know what i'm doing wrong here or is it something wrong with the mesh itself possibly? I can upload whatever needed to help figure it out. For now here's the photos of my textures and the actual issue.

Don't be embarrassed, we all got to start somewhere! The diffuse map must be grayscale. Open the image in your photo editing program and completely desaturate it. The mask texture looks good, but I would personally make the red and green bigger.

I can't see it very well, but it looks like your multiplier is not be in greyscale as it should be. You should aim for RGB values around 128, 128, 128 or as close as you can around that range. Additionally, typical good practice as well for RGB mask is to fill it in entirely and not leave transparent space.

Here is an example of a multiplier, mask, and overlay for a calendar object:

It looks like you've cloned the pearl earrings, which have only one color channel enabled by default. If you scroll down in the Texture tab in TSRW, ensure that the "Enabled" value is set to "True" next to the second color channel. Also, Multipliers should be grayscale.

I tested this to see if it would cause any issues and it doesn't appear to, but your green is just barely not the correct green (should be hex code 00ff00, yours is 00fe00), so I'd make sure your green is a pure green (or you could try yellow (ffff00)). So if you're sure the color channel is enabled correctly in TSRW, then maybe it'd be worth ensuring your colors are correct (though I'm not sure such a small difference would matter).

For reference, the channel colors are (in hex codes):

Channel 1, Red (ff0000)
Channel 2, Yellow (ffff00) or Green (00ff00)
Channel 3, Magenta (ff00ff) or Blue (0000ff)

With the 4th channel being done by editing the alpha channel.

And this is really just a tip and wouldn't be the cause of the problem, but a recolor mask that doesn't have a 4th channel really shouldn't have any transparency. What I typically do is color in the areas for the Yellow (ffff00) (Green in your case), and Magenta (ff00ff) (for the third channel, if needed) in a separate layer, then color the entire layer below them Red (ff0000), merge the layers together, and export DDS DXT1.

Sorry for the late reply, thank you guys for the help! Managed to get it working finally!