nodeMCU boards in one location and HA on other

Hello good people,

I have a Home Assistant on location 1, with nodeMCU boards (sensors) that communicate with HA (on pi4) over WIFI and feed data into it (every 10 seconds). I use HA to automate some actions based on this data. It’s all under this HUAWEI LTE router/ap, and I use LTE connectivity to access HA over WAN when I’m not at that location.

However, I need to move the HA server to another location but leave the sensors where they are, which means sensors will lose connectivity to the HA instance and will no longer be able to feed data into HA as they will not be under the same network anymore.

What is the easiest way to achieve this without additional HW so both LANs can see each other? I tried Zerotier, seems that it won’t work as all clients have to have Zerotier SW installed and my shitty router at location 1 is not able to install any packages. Maybe VPN?

I’d like to avoid cloud-based MQTT, but if there is no better option…

What to do, gentlemen?

Resolved with cloud MQTT