Not really, the designs on the iPhone's are obviously similar but the hardware is not the same, the display on the OnePlus 5 is a the exact same display as on the OnePlus 3, the displays on the OP5T and OP6 are exactly the same but stretched.
It's amazing they've got away with it really.
The hardware is different between the OnePlus 6 and the 5T, except for the screen.