I'd use the free "All2MP3" utility to convert the WMA files to mp3 files.
Then they should be playable by almost anything on the Mac.
What you're going to need:
All2MP3, of course.
But...
WARNING WARNING WARNING
DON'T download All2MP3 from the original source, because
they "package it" along with crapware that will also install. Why they do this, I don't know.
Again,
DO NOT download from here:
Help you to convert your music to WMA, MP3, AAC, WAV, FLAC, OGG, AIFF, Apple Lossless format & more for free. Easily converts music files between 25+ audio formats in high quality. Runs on macOS.
tresrrr.com
DO get a slightly older version of All2MP3
from here:
Tucows offers Domain Name Services, Fiber Internet Services and SaaS through our businesses Tucows Domains, Ting and Wavelo. We're a tech company headquartered in Toronto, Canada, making the internet better since 1993.
www.tucows.com
The above URL will download the app and NO "crapware" along with it.
Also... once you have it, DO NOT choose to "upgrade". It will probably download the installer that has the crapware in it.
Now... having said that, a good version of All2MP3 will do the job easily.
What to do next:
Create a folder on your desktop. This will be where you convert the files.
Copy a WMA file or two into the folder. You want this folder OPEN on the desktop, so you can see the files. Don't make the window too big.
Next, open All2MP3. It will open with a modestly-sized window on your desktop.
Next...
"Grab" one of the WMA files with the mouse, and drag-n-drop it into ALL2MP3's window.
A new dialog opens with some options.
Select the highest quality conversion.
For a destination, use the same folder that the WMA's are in (you can move them wherever you like later on).
Then, click convert (or whatever the button is named, can't remember).
The conversion will take a few moments (or longer, if the files are large).
When done, you should see an mp3 file with the same name in the folder.
Try it, and see how it plays.
Does this do what you need?
If so, convert all of them that way!