If you want to use Docker to build cross-platform images, the first step is to enable QEMU to run images targeted at others architectures via emulation. I assume you have installed Docker CE and its containerd runtime as described here, and are running on a x86_64 host.
Within current distributions of Linux, there is a kernel component called netem that can be used to test and simulate the type of issues one would see over a Wide Area Network. This component is managed with a tool called traffic controller. This can be helpful during testing/troubleshooting to emulate the network latency or packet … Linux: Introducing latency and packet loss into network for testing