In theory, a device such as this could add 2-4ms round-trip latency in optimal conditions. In practice, even with optimal conditions, these companies have not perfected this technology, and they are not usually targeted towards gamers.

Wirecutter has a write up on these sorts of devices.

I would honestly just recommend a long HDMI cable that you run along the perimeter of the room. You can get flat hdmi cables if you think that will look better - I’m renting and am running flat white ethernet cables taped with white duct tape to the white baseboards throughout the house, and it looks pretty clean.

Otherwise, buy from someone reputable so you have less hassle returning it if latency is clearly an issue.