this is about switch vlan with hardware offloading, not bridge vlan

I assume the answer is "no" but I will ask it anyway.

Is it possible to have wirespeed with intervlan?

My understanding is; To be able to do intervlan, vlan need to go in the switch-cpu which mean it's not possible to reach wirespeed for a file copy using one thread; scenario nas --> pc, windows 10 explorer copy of one file max out at ~325mbits/sec instead of ~1gig/sec, seeing cpu going at 100%. So it's impossible to have wirespeed.

Not with atheros 8327
Read here https://help.mikrotik.com/docs/display/ ... Offloading