Is there a text tool to edit project files?

I am trying to edit the project file data to reference and updated version of a plugin instead of the old version which is named differently without opening the project as it will set all parameters to default.

When I open it in notepad and excel, while some of it is in plain text, many of it is not and I have no idea how to interpret the encoded symbols.

Does anyone know of a tool or trick that makes viewing and editing these files easier or at least decodes it into plain text properly?

You mean the data of a *.cpr file? You can’t just edit this is a text editor or any other program. You’ll have to make these changes within Cubase itself.

Unlike the settings files (which are in XML), very little of the data in a project file is editable plain text. Since it can contain data that plugins save (in God knows what format), you’ll need a HEX editor, be comfortable with hexadecimal numbers, and have Steinberg provide you with the format of a .cpr file, and get the plugin devs to provide you with the format of their data.
Be easier to open a project with the old plugin, take a screenshot, and set it up in the new version.

Why do you say this? It shouldn’t. Are there specific “parameters” you are referring to?

if you replace a plugin in any daw all of the plugins parameters get wiped. It would have been okay if I was using presets AND remembered the names of the presets but that’s never the case. There is also the case of sometimes needing to edit a project file to remove a bad plugin from a project that crashes as soon as you try to open it. works great editing ableton project files. Bitwig also loads plugins is separate processes so they don’t crash the whole DAW. This is an area of Cubase that needs improvement

Short answer, no you can’t manually edit a Cubase project file. These are created in a non-human readable format. Even if you would be able to figure out how to reverse engineer the .cpr file and make changes to it, it would not be recommended for what you’re trying to achieve.

VST plugin parameters are defined by the plugin maker and stored as a long list with ascending ID numbers. VST hosts, such as Cubase, do not care what VST Parameter #0004 is or what it does.

If a plugin creator decides to create a new version of their plugin with a new plugin ID (or plugin name) as in your case, it is most likely because there isn’t full compatibility with the older version. There is nothing that says that VST parameter #0004 that was defined as “Volume Level” in the old version is “Volume Level” in the new version.
So, if you were to successfully change the plugin referenced in the .cpr file to the new version and there are parameter mismatches, it could cause program instabilities.

So what can you do? If the plugin in question has its own native preset handling, you might be able to store the settings of your older plugin in a new preset and load them in the newer. (Note that this will likely not work by using the universal FXP/FXB format.)
If the plugin does not have native preset handling or it is unable to share presets from the old version to the newer, I would write the manufacturer and ask for advice.

To clarify, you are saying that it is the swapping in of the new version of the plug-in that clears the settings, but if you simply open the old plug-in nothing gets changed - right?

Have you tried opening it up in an older version of Cubase, where the plug-in still functions, and then as @mlib suggests save it as a preset, or even take a screenshot of the settings.

no, replacing the plugin within the daw wipes the parameters. it is not possible to reinstall the older version of the plugin which is why i am trying to edit the project save file using an external editor to reference the updated version of the plugin with a different file name, which ive had great success with fixing ableton projects. the older version of the plugin is long gone and out of the question which is why i need to do this. it has nothing to do with the cubase version. it is not outside of the realm of possibility. i will continue with trial and error and develop my own tool to unbrick DAW projects.