Discussion about mobile hotspots
Discussion about mobile hotspots
You can simply link a USB device straight to your computer. All phones and portable hotspots I've tested work with USB tethering. If your mobile modem includes an Ethernet port, connecting directly at that point should eliminate Wi-Fi as the issue. The 5G modem is unlikely to accept USB Ethernet adapters, so that won't help much. Mobile and wireless connections are naturally unreliable and unpredictable. This is just how they function.