Sebastian's my favorite vanilla character, so I really appreciate you taking the time to find mods dedicated to him! If you continue this as a series, maybe Haley or Penny could be next?
I've tried installing these through SMAPI with all of the requirements and these portraits never work for me. Are they supposed to go into the mods section because any time I try to replace the portrait files in the portrait folder, it bugs out my game and won't load until I put back the original files.