What investigations did you make about your desired hardware?
Depending on the hardware revision, this device will not even route 300 MBit/s without any kind of QoS[0] or hit a brick wall with sqm/cake around 200-250 MBit/s at most[1].
What does the ToH say about this device[2]?
With 300/30 MBit/s and QoS, you should have a good read at[4]:
While I can understand where you're coming from, this
is not quite what you're looking for either, nor easy to implement.
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[0] QCA9563 in rev 1.x, 2.x
[1] mt7621a in rev 3.x
[2] Hint, it isn't supported - and never will be. Unsupported SOC and not meeting bare minimum system requirements.
[3] mt7622bv, filogic 820/ 830 and ipq8072a+ would probably cope with that, but without much of margin for future speed increases; details will have to be tested.