Pattern Help

Hi everyone,
'm new to this forum but I have been knitting for 45 years and my brain just went blank.
I found a sweater pattern the I would love to make for my granddaughter but the problem is when I ordered the pattern I was going by the picture of the sweater only to find out when I got it that it is done in Emu Yarn (have no idea). I did some research and found out that this yarn is comparable to light worsted weight yarn (category #3).
My question is this - does anyone know how to change this pattern so it can be made in 4 ply knitting worsted? If not does anyone know where I can find a sweater pattern with diagonal stripes for a teenage girl - size 10?
Thanks - Any suggestions would be helpful!

What is the gauge listed for the sweater?

If you do a gauge swatch and a little math, you may be able to use the same pattern, but maybe go down a size.

The gauge is 22 sts and 30 rows to (10 cm) 4 ins.

You could make her one in a smaller size with the worsted yarn. Figure out how many sts/inch your yarn gets with the needles you want to use, and how many inches around it needs to be. Multiply sts/inch times inches and see if there’s a size that has that many stitches in the chest area (front and back combined). The closest size would be the directions you follow, adding extra length to fit your GD.