I'm entirely new to the modding scene, and I wanted to make a certain child clothing item (specifically a bottom) into something that can fit a teen or (young) adult. Is this possible? And if so, how? Thank you so much <33
Doing a complete conversion, shape plus texture, is possible but not really a beginner project unless you're familiar with meshing. The basic process is to extract the mesh, resize it, match the waist and ankle seams to the rest of the adult body, import the modified mesh into a cloned adult clothing package, plus extract the child textures and import them to the adult package.
It's going to be difficult unless you have some knowledge of Blender.
The other alternative, if you don't want to tackle meshing at this time, is to find a similarly shaped item of adult clothing and extract and adjust the child texture to fit the adult. It's not hard if you have some experience with an image editor. Here's a tutorial on how to do that: https://www.youtube.com/watch?v=wshaLDZqiZE
Let me know if you have questions or need more help.
Please do not PM me with mod, tutorial, or general modding questions or problems; post them in the thread for the mod or tutorial or post them in the appropriate forum.