Huawei E3372 Hi-Link doesn't work with macOS Catalina
Huwei has posted an update for mobile sticks drivers for Hilink products you can use this : https://consumer-tkb.huawei.com/tkbapp/downloadWebsiteService?websiteId=1697201
for the other devices (that use mobile partner or mobile wifi): visit this link https://consumer.huawei.com/en/support/search/ and then click software section you'll find the driver for your device
I flashed my Huawei e3372h-153 with Stick firmware and I'm able to connect via modem in Catalina. Instructions here.