If you are so determined... let's begin. I recommend you to use Notepad++ for its bare minimum ability to see the values and search function.(also useful for professional things if you are into that)
It can be downloaded from below:
https://notepad-plus-plus.org/download/v7.3.3.htmlFirst, you must have a save file. Your save file can be located at: "C:\Users\[username]\Documents\My Games\Underrail\Saves" if you are running the windows.
Always make at least one more save file in case you screw up this process.What you want to find here in those individual save is file named "global.dat". It is encoded in some way and must be processed in some way. Luckly we do have a way.
Go to this forum page where epeli put together some tools. What we are looking for is 'unpacker".
http://underrail.com/forums/index.php?topic=2753.msg14299#msg14299 -> unpacker.
Select your save file's "global.dat" using this unpacker. it will download the unpacked version -probably named as "global_unpacked.dat" or something.
If you have installed Notepad++, you will be able to right click this file to see the option "Edit with Notepad++". Please edit this unpacked file with Notepad++.
Now, use search function(Control + f key) to look for the feat section. the file is long as we don't have all the time to look through all of them.
Search for your character's existing feat names. it is the easiest way.It should look like this:
As you can see, your character's list of feats should be in this section of the text file.
What you need to do is find the undesired feat, and replace it with feat you want.
Unfortunately you probably do not have the full name(for example, paranoia feat's full name is [BS]paranoia. See the picture above. ). Please tell me the feat you desire. I should be able to find out the true name for the feat.
But even after replacing the feat, it isn't over! You must re-package the unpacked file.Go back to the unpacker and select the "global_unpacked.dat" that you just edited. It will repack the file and download it again. (its name is probably like "global_unpacked_packed.dat")
Change the name "global_unpacked_packed.dat" back to "global.dat". Replace the original "global.dat" in the save file.(it has to be the same save file from few steps above.)
And voila! your feat is replaced.