This is how I set it up.
The camera itself is mounted on a little desktop tripod, with an adjustable gantry that lets you twiddle the position of the camera. In practice the gantry isn't really necessary. The ring light is mounted on a tripod with a double ball joint dohickey, and the spot light is mounted on a smaller, flatter tripod with the same type of double joint.
The ring light gives you a relatively flat base lighting and the spot gives you the specular reflection and anisotropic reflection from the surface finish. The stack of books just raises the subject, and the copper bar is a paperweight to keep the books flat. I'm using black construction paper as a background - I bought a packet of it off Amazon. Other folks like microfibre cloth or velvet, or you could do a light background with white paper or card. You'll have to provide your own sovereigns.
The PC screen in the background is significant as I'm using the camera through tethering software. Sony provides a tethering application for their cameras called Imaging Edge - in fact, the primary reason I got a Sony camera was that it had good support for tethering. In theory the A6xxx series should also play nicely with open source photo applications, but I haven't been able to get Darktable to mount it (although it does recognise the camera). Imaging Edge is free and seems to work fairly well with a few limitations.
It doesn't have support for automated focus bracketing, as far as I can tell. There are third party apps that theoretically do this. Currently I haven't thrashed out a solution for this. You would need this to do focus stacking if you wanted to take a coin from any angle other than straight on. Photoshop will do the focus stacking if you have the images, but I haven't worked out a way to do this with the A6400 under tethering control yet.
It will export to JPEG, but only at relatively high grades (i.e. images too big for the measly size allowance supported here). I had to import the files into photoshop and then re-save with a lower detail setting. Fortunately you can still get decent image quality at settings that will produce images small enough to upload here.
Sony's native raw format (ARW) isn't directly supported by Photoshop, although it is supported by Darktable. Fortunately Adobe publishes a conversion utility that will export DNG files that Photoshop can read through its RAW file importer.
On the plus side, it works well with the lighting and it's far easier to get decent pics with than the smart phone. The camera cost me £650, which is about as cheap as I've seen it. I got it from a grey market box shifter but you might pay closer to £1,000 from a real camera shop. The lens was £185 from another online retailer.
In practice a secondhand A6300 would do the same thing just as well, and I did seriously consider getting one. You can get those for about £350-400 off Ebay or other secondhand vendors. The tripods and lights would be about another £200 or so in total, although I have some other lights as well not being used in this setup. I think the price for this sort of setup could be kept to about two sovereigns if you went with a secondhand camera body.