STHeiti Cleaner.

RemovingSTHeiti.sh

#!/bin/bash
# At least works with macOS 10.12 - 10.14. Do not use this with macOS 10.11 and earlier.
# RUN THIS SCRIPT UNDER RECOVERY MODE.
# !! REMEMBER to change the next line to make sure it fits your actural system volume label.
cd "/Volumes/Macintosh HD/"

# Applying International Text Styles to Japanese GUI of current iTunes.
cp "Applications/iTunes.app/Contents/Resources/English.lproj/TextStyles.plist" "Applications/iTunes.app/Contents/Resources/Japanese.lproj/TextStyles.plist"

cd "system"

# Remove "Heiti SC / TC" collection files (shipped since Snow Leopard) and their derivative definitions.
find "$(pwd)" -name "STHeiti*" -type f -delete

# Remove STHeiti antiquities shipped with macOS Leopard.
find "$(pwd)" -name "华文*黑*" -type f -delete
find "$(pwd)" -name "STXihei*" -type f -delete

# Remove SIL Hei antiquities shipped with macOS 10.02-10.04.
find "$(pwd)" -name "Hei.ttf*" -type f -delete
find "$(pwd)" -name "SIL-Hei-Med-Jian.fontinfo" -type f -delete

# Remove LiHei Pro.
find "$(pwd)" -name "儷黑 Pro.ttf*" -type f -delete
find "$(pwd)" -name "LiHeiPro.fontinfo" -type f -delete

# Remove BiauKai shipped with macOS which has lack of compatibility exchanging MS Office files with Windows users.
find "$(pwd)" -name "BiauKai.ttf*" -type f -delete
find "$(pwd)" -name "DFKaiShu-SB-Estd-BF.fontinfo" -type f -delete