There were a few Topps Star Wars Galaxy card sets with die-cut sketch cards in them, and in those pre-Disney days, many of the sketches were a little out there, even by Star Wars standards. I pulled a handful of images from eBay, just to show you what I'm talking about:
|Sketch by MCA - Evil Design|
|Sketch by Ritzy Periwinkle|
|Sketch by Burt Banger|
|Sketch by KaToPe|
There's no way those get through the approval process these days. I honestly think many of them are pretty cool, like that Obi-Wan in the upper right, but at the prices these go for I'm not a buyer at the moment. But there are plenty out there if you want to look for them. I just wouldn't suggest taking any mind-altering substances beforehand, as I think some of these could trigger a bad trip.
I had a more conventional sketch from Star Wars Galaxy on my eBay watch list for a long time, and I finally added it to my collection a few weeks ago. This is a Leia sketch done by artist Martin Hsu. I don't think he does a lot of trading card sketches, but it seems like he sets up shop at conventions with some regularity, and he's got a website, a Twitter, and an Instagram.
There is actually a little more color to Leia's face than my crappy scanner picked up, and I think Hsu found a pretty cool way to use the shape of Admiral Ackbar's head to draw Leia on the flipside. This was a fun addition to my Leia sketch collection, and I'm glad I was able to pick it up before someone else got to it.