The Lenovo LI2264d (or LI2364d) monitor doesn't support VESA mounts directly, but here's one way to mount it on a VESA mount. All the parts can be bought for < $10 at stores like Home Depot, and takes a couple hours at most to put together.

First, take apart the vertical part of the stand that came with the monitor. There is a black plastic cover that can be taken off by removing the screws, revealing the assembly inside.

We want to reuse the bare metal part that fits into the monitor body. I used a 5/16“ wrench to reach into the assembly and unscrew the hex nuts.

After disassembly, you should also end up with two screws and a bunch of washers/spacers. The washers are important because we'll later use them to match the width of our bracket to the width of the monitor mount.

To make the bracket that attaches the VESA mount to the monitor mount, I used two corner braces. The 3” ones from Home Depot worked for me because, 1) the pre-drilled holes are big enough for the screws that fit into the monitor mount, and 2) the distance between the edge and the inner holes, plus the width of the monitor mount, is close to the 75mm distance on the VESA mount.

First, I attached the braces to the VESA mount plate that came with the VIVO monitor stand that I'll be using. The assembly consists of M4 screws, hex nuts, and a couple washers

On the other end of the bracket, line up the bracket with the monitor mount from the monitor stand assembly. Use the original screws, hex nuts, washers, and spacers to secure the parts. It may take a little effort to fit them together. Here's the assembled bracket with VESA mount plate on one end and the monitor mount on the other end. This particular assembly actually didn't work because it was too wide for the recess in the monitor body that you fit the monitor mount into. I had to take this apart and move the outside spacers to the inside for it to fit.

At this point I thought I was done, but of course when I tried to fit the monitor mount onto the monitor body, it wouldn't fit because part of the bracket was pushing into top wall of the recess on the monitor body. Ugh! I had to cut two grooves into that wall to let the bracket through.

And with that… the mount finally fits!

It's working pretty well with the monitor stand. The monitor doesn't weigh that much, so I don't expect any problems for regular landscape usage. Actually, the mount feels sturdy enough sideways that you might even get away with using it in portrait.

Edit: I've since switched the corner braces to smaller braces from Menards. These braces also fit the 75mm VESA mounts, but require some additional spacers to give enough clearance to the back connectors. One benefit of the smaller braces is they give a greater degree of tilt adjustment.