Sample rate issues (Soul Worker)

[DrawingKyo]

Recently, I have been able to rip voice files from a game called Soul Worker.
At the moment, all files are cleanly in a wav format.
The only problem lies in the fact that most rates (Hz) are completely off.

The files need to be changed to 88200 Hz, but when I try to use a mass file converter, the rates change but the sound itself does not.

Anyone have any programs that could help change the rate along with the sound?

Edit: Using Audacity to manually convert them all is impossible because there are over 5000 files.
Edit 2: Solved Issue: used Audacity to fix the issue but now another problem has arisen.