Pictured: Intel and Qualcomm to offer 5G Modules for M.2 Slots
Thales | Starter Kit 5G Data Card | L30960-N6902-A100
5G Home Router: 5G M.2 PCIe Module Will Be Released Soon at Seeed Bazaar Online Shop - Latest Open Tech From Seeed
Amazon.com: Sim Card Modem USB to Mini pci Mini pcie USB Adapter Pci-e Sim Card Mini PCI-E sim Card to USB Adapter with SIM Card Slot for WWAN/LTE : Electronics
Pi add-on offers M.2 for 5G and mini-PCIe for 4G and NB-IoT
U0403A (mini card Rev 2.1 4G / 5G module to USB 3.1 Adapter)
4G 5G Modem Adapter - Mini-PCIe to M.2 - The Wireless Haven