I've checked the Downlad specs of your Router - Huawei B625-261. Its a 4G+ CAT12 Download Spec which is 600Mbs Max, although Huawei claim max speed of 720Mbs probably due to Huawei's Internal MiMo Aerial design.
So first off you never going to get these maximum speeds on a 4G Network in real life but it does prove that the Router is capable of giving a good throughput and should be capable of similar speeds that you are aquiring from your Phone in the same location.
Obviously if your Phone is 5G, your in a 5G Coverage area and our Plan is 5G then you cannot expect like for like speed test results but by switching the phone to 4G Only, then doing some speed tests, swapping Sims etc should give an understanding what to expect in the same location.
If both your Plans are on EE Unlimited then there are no speeds restrictions on these Sims.
The other thing to be considered is Speed Loss through the WiFi Signal, it's never going to be as good as speed testing on the phone, as the Routers WiFi will play an additional obsitcle in the overall speed. You can do do additional test regarding the WiFi side by putting the Phone into Hotspot Mode and testing that way as well as using a Direct Cable connection to the Router thus bypassing the Routes WiFi and Speed test that way.
