Task: Recursively rename all files under /system/folder2 replacing special with regular.
Command: find /system/folder2 -type f -name '*special*' ! -path '*/special/*' -execdir bash -c 'mv "$0" "${0/special/regular}"' {} \;
Equivalent command: find /system/folder1 -type f -name '*special*' -exec bash -c 'for f; do mv -- "$f" "${f%/*}/${f##*/special/regular}"; done' _ {} +