It doesn't even have an OS. The launcher would have to dynamically patch the games. Not impossible, but a lot trickier, I guess.

Problem is that from what I've read, the system firmware is embedded in a module that also serves as WiFi. There is a chance that the firmware could be hacked to enable WPA2, but probably not WPA3.

DS games didn't even worked with WPA.

Only DSi Enchanced and 3DS games supported WPA2 at best. Your best bet is using older router with OpenWRT to make WPA3 to WEP bridge.