USB C is normally able to work as a kind of display port. But i dont know if this is also true for the oneplus 5 phone, because you see: you also need the original cable to use quickcharge/dashcharge and so on.
Maybe it does not work with a oneplus 5 device
But you can try one more thing: install 'Slide sync' on your desktop pc/laptop and on your mobile.
Then you can connect your lapotop/computer with the tv.
Slide sync allows you to see your smartphone screen on your pc and controll it.
then you simply connect your tv with your pc via hdmi and done.
Besides the cable or adapter, you also need software and hardware support from the device.
Unfortunetelly, OnePlus 5 does not have any kind of TV output.
So, you'll have to use another method, wifi connection > chromecast or something else.