Hi Sprout,
SSH packets are encrypted for transmission. It takes time to negotiate the algorithm between the device and STA. Maybe you could try to change the algorithm.
First, check the current algorithm by that command “display ssh server session”after login successfully
If it is complex, You can run the ssh server key-exchange command to change it, or undo it directly.
https://support.huawei.com/hedex/pages/EDOC1000170178AEI0315V/12/EDOC1000170178AEI0315V/12/resources/software/nev8r9_vrpv8r15/user/vrp/ssh_server_key-exchange.html?ft=0&fe=10&hib=9.1.4.3.67&id=ssh_server_key-exchange&text=ssh server key-exchange&docid=EDOC1000170178

I hope it helps.