How to colorize photos with user selected colors (treatment/grade) as seen in Instagram reels.

There's a technique I've seen on some Instrgram reels that I can't tell if it's real or if it's made up for Instagram. Appears to be for Lightroom, but posting here as I don't know which version of Lightroom or if it could also be Photoshop, or there may be alternate approaches. This is not the Colorize Neural Filter.

In the Instagram reels what appears to be happening is that a file is converted to B+W (assume staying as RGB, not greyscale), then a set of colors, looks like 5 color patches that have been pulled from, lets say, a movie still, are then applied to the B+W photo, resulting in a new color treatment (grade). The way the reels are filmed makes this look like it's not done with Photoshop color mapping though it's maybe a similar process, but like it's done with Lightroom and that it's almost a "choose mapping colors, click and apply" process.  Can't tell if Classic or the cloud version.