Is 1080p sharp enough on a 27-inch screen?

It is usable for documents and web work, but text looks softer than on a 24-inch 1080p screen or a 27-inch 1440p one. If you read small text all day, a higher resolution at this size is the better choice.

Can I connect a laptop and a desktop at the same time?

Yes. USB-C, HDMI, DisplayPort and VGA are all present, so you can leave a desktop on one input and dock a laptop on USB-C. You switch inputs manually; there is no mention of built-in KVM.

Does the USB-C port charge a laptop?

The specs list USB-C but give no power-delivery figure, so do not assume laptop charging. Check the port's wattage before relying on it for a single-cable setup.

Is it good for gaming?

Only casually. 75 Hz and a 1 ms overdrive rating suit slow-paced games, but fast shooters want a higher refresh rate and lower real input lag.

Can I mount it on an arm or wall bracket?

Yes. It is VESA-mountable and the stand is height-adjustable, so it works on a desk or on a monitor arm.

Typically the monitor, stand, and the cabling the listing specifies. Confirm which cables are included, since VGA, HDMI, DisplayPort and USB-C are all supported but not always all supplied.