I was trying to work out a way to do Tunisian Entrelac a certain way, and also trying to figure out how to do short-rows in Tunisian crochet by missing stitches on the right-hand side of the fabric instead of always on the left. I came up with this tutorial on how to work the Tunisian Simple Stitch backwards and still have it look like the Tunisian Simple Stitch!
You'd do well to be comfortable with the Tunisian Simple Stitch before attempting this!
I started with 10 stitches, and did 3 rows in the usual way:

Then slip-stitched across, just like when you’re binding off. This was just to get the hook to the left side of the piece:

Turn (this puts the yarn on the wrong side… I need to play with this a bit)

Now flip the piece up so that you can see the front and insert your hook into the second vertical bar (you may want to count bars the first time you try this, just to be sure. I counted 9 from the end)

Then yarn over and pull a loop through.
I found it easiest if the working yarn was above the stitch (but since you’re working upside down, it’ll be below your hook) like this:

then lay the yarn over the hook and pull the yarn through
Do that for every stitch:

then work the loops off in exactly the same way you’d normally do it
It’ll look like this from the back:

And this is it from the front:

Here is the 3 rows worked normally and 3 rows worked backwards, looking at the front:

I then slip-stitched (working into the right side of the piece, which was tricky, but worth it, I think) across to get the hook back to the right-hand side of the piece and worked 3 more rows in the normal way:

This is the back (there is a ridge of slip stitches between each change of direction, you can sort of see them)

Now, I don’t know if you noticed, but you can tell which row was worked backwards because of the way the vertical bars stack. It sticks out in this swatch, but I don’t think it will be as obvious in most applications, and I don’t think it really matters when applied to Tunisian entrelac, as the sections worked backwards will be worked at a right angle to the sections worked the normal way.
You can make a really neat looking fabric using this technique combined with short rows. More to come on that!