Hello,
Unfortunately, we do not sell products with built-in SIM. There is a possibility for our customers to modify the devices to support E-SIM but it requires hardware changes and for that, you would need to contact Teltonika's sales manager.
Regarding your question about 5G, we will definitely manufacture 5G routers in the future, but right now I cannot share any exact dates and plans as 5G is brand new technology and not yet supported widely in the world.
Regards.