There is a lot of shareware and freeware (jEdit, Notepad++) to do complex search and replacement in files but none is supporting these kind of operations in zip files spread across many subdirectories. Luckily Oxygen Editor can
Do case sensitive or insensitive searches,
Search and replace across multiple files in multiple subdirectories,
Search and replace also in ZIP files,
Advanced regular expression search/replace,
Is free to evaluate for 30 days!
Use the Menu "Find" and select "Replace in Files" or use the shortcut CTRL+SHIFT+H
Oxygen can also create backup of every changed zip files, as xxxxxxx.zip.bak as shown in the picture above.