Fake louvers can be made with a table saw and plunge router.
make saw tooth cuts with two passes on the table saw, one at 90, one at 45, so they meet close to the other side. (you want to end up with half an "M" not a "V" cut) Don't cut all the way through as you need it to stay together.
cut off two 1" or so strips (width as desired) from the sides. then use the router to open up the bases of the cuts from the back side, leaving an inch or so on each side uncut.(to keep everything together) if your angles and measurements are right, you can then flip the 1" offcuts and glue them on to make a finished edge on the saw cut side which will be the outside.
If you don't have a plunge router, you can finish cutting the louvers with a table saw by making a double pass at the top (bottom) of the V. Or even repeat the whole saw tooth cut pattern on the back, which will provide a more realistic lover look. The router leaves the back side flat with slots (stronger louvers, but a slotted, not louvered look from the back)
Can be easily made to fit angled sides the same way, just make the flipped parts wider so you can cut the whole thing to shape.