AXT 1800 (slate) - additional way to internet using a SIM card?

[gfondeur]

First thing first, the AXT1800 ist not a mobile (LTE/5g) travel router, refer to this post

@gfondeur

First thing first, microSD (TF card) and microSIM card (Sim card) are two different things

Second, the AX1800 (Flint1) the AXT1800 (Slate AX) are NOT cellular routers (4g/5g routers) aka routers that use mobile operators waves to serve you a wifi connection, for that look at:
GL-X2000,
GL-XE3000,
GL-XE3000,
GL-E750,
GL-X750,
GL-XE300,
GL-X300B

Hope this helps to clarify