The Replace Text script is made for renaming files, not for modifying the content of files in an entire database.
Convert a wikilink target into an item link without the laborious process of opening the target, copying, returning, and editing the link? Just adding copy item link of target to the context menu of the link might be enough.
I’m not sure if it’s what you’re wanting but @pete31 posted a script that may be useful to you.