So I see there's a bunch of quasi-useful information offered here and realize you still might be a tad confused. I hope this helps:

First, understand that "Arca Swiss plate" is a term relating to what has become a standard system for quick-release plates and clamps. And while Arca Swiss (the company) manufactures some outstanding ball heads that use this system a number of other manufacturers, like Really Right Stuff, Kirk and more also offer lens and camera body plates as well as clamps that can be fitted on the tripod. The Wimberly gimbal head, as you have seen, uses the Arca Swiss style clamp.

You say you want a plate for your D850, but you are not going to want to mount the camera body onto the gimbal head. Gimbal heads are designed to enable you to swing the camera/lens rapidly to follow moving objects (typically birds in flight) - in order to do that, the weight of the camera+lens needs to be centered on the clamp mount of the head. Unless you plan on using a short telephoto lens (which is rather pointless on a gimbal head) you will be making use of the long lens' "foot", so the bracket you will want in order to use the gimbal head properly will be one for the foot.

Personally I am a fan of RRS gear - though I have certainly used others. If you go to their website (https://www.reallyrightstuff.com/) you can see they offer plates for all kinds of Nikon (and other) long lens feet (https://www.reallyrightstuff.com/plates-brackets/plates-brackets-lenses/nikon-lenses), many of which have a lip of some sort that will prevent the lens foot from twisting out of alignment should the screw loosen a little. They also offer camera plates for specific models of camera - I've had a dozen of these over the years - which are custom designed as opposed to being generic in style. They can get kind of pricey, so if budget is a concern certainly you can find less custom camera plates.

I mention the camera plate side of things even though with the gimbal head you will need to use a lens foot to properly balance the set up because you might, at some point, want to get a ball head for the tripod for use when you are not going to be shooting with the long lens but still want support. Using the quick release system certainly makes operating a tripod setup much quicker and easier, so it's something to consider. Here again, a nnumber of manufacturers offer ball heads that use the Arca Swiss standard clamps, including Arca Swiss themselves (https://www.bhphotovideo.com/c/product/1373798-REG/arca_swiss_8501303_1_cube_c1_gp_geared.html?sts=pi-ps&pim=Y - if you've just won the lottery). Seriously, though, RRS, Kirk, and a gaggle of others (I have a bunch of heads and like the Acra-Tech brand as well, myself) so you can select from a number of options. The entire point is that the Arca Swiss mechanisms are standardized such that any of the clamps will work with any of the plates.

I hope that helps.

I don’t think there is anything that compares to what you get with Lightroom. It’s really hard to compare to others because for $10 a month there is not a single program that give you all Lightroom does.
A partial list is:
Lightroom CLassicwhich is the version that resides in your computer
Lightroom CC which is the software that resides on your computer or mobile device for accessing Lightroom in the cloud.
Lightroom.com which is the browser based version that allows you to access Lightroom from any computer in the world
20 gigs of cloud storage
Adobe Portfolio which essentially is your own website or actually up to 5 different websites. With the ability to use your own URL if you want or your own domain name if you choose. All included in the price. This alone is worth more than $10 a month.
The other thing you get with lightroom is the available plugins. I don’t believe any other competitor has as many available plugins.
Plus you get Photoshop thrown in too. Not a lite version but the full version.

With all that said you didn’t really state why you are interested in an alternative and there are many valid reasons. The most often compared head to head would be Capture One. I would say Capture One is becoming an industry standard also. If you are just looking for a software that basicly does what Lightroom classic does that would be the closest

Here are a few things to consider about print surfaces.

Glossy and luster surfaced prints, especially in low key images, where the rendition of subtle shadow detail is important, will work exceptionally well. A dead matte surface tends to diminish shadows details especially where the image is printed down to maximize highlight detail. Even a glossy or luster surface print that has been lacquered with a matte spray or displayed behind non-glass glass can "gray down" and loose subtle shadow detail. There is a reflection reduction glass that is sandblasted only on one surface that somewhat minimizes this effect. A high hey image, one that is comprised of the brighter end of the grayscale or of lighter printed pastel colors can be on matte paper or matte lacquered without loss of quality.

Another factor is the style and subject. Some subjects are enhanced by a textured surfacer such as mock linen, canvas, silk, satin, or other textures whereas, in other particular subjects, the texture may become a distraction or seem incompatible. For example, a portrait of a made wit a weathered complexion or a landscape including a rustic old barn may be enhanced with a burlap-like texture whereas as a still life of a violin or a commercial illustration of silverware or surgical instruments my benefit from a smooth or glossy finish.

A print with a modern motif in a highly polished (chrome) frame and a high gloss print surface would be a good match. A traditional portrait or still life can benefit from a tapestry-like texture or a painterly kind of material such as canvas. Image a picture of mechanical tools- wrenches, ratchets, sockets, etc., print on glossy metal!

Think of the subject, the manner of display, the frame as a finished piece and select the material accordingly.

A far as preservation, sticking to the glass, fading, etc., that is not so much a matter of surface but the use of archival papers, pigmented inks, mattes, framing materials, archival framing techniques using mattes and spacers, conservatory glass, protective lacquers and varnishes, and protecting all prints and artwork from moisture, heat, and excessive exposure to ultraviolet light.

We always speak about dynamic range. Many of us view all our images on a screen. Even if the screen is correctly calibrated, we are looking at an image comprised of illuminated particles of one kind or another- same as viewing transparency by transmitted light. Prints are viewed by reflected light so the color, density, and range are affected by the volume and color temperature of the light and the incredible range that we love on the screen turns out to be missing and disappointing in a print, In many cases, the SURFACE will make a very discernible difference.