Yes, you can definitely do that .... I sometimes sketch on the design that I want.
What I find works best (for me!) is to not feel bound by the sketched design .... I use it as a guide, and let the FMQing be somewhat free. So while I have marked for it to swoop in a specific way, I may end up swooping a bigger one, or put in an extra curl or whatever as I go. Or I may have sketched a flower and then when I FMQ it, the flower may be a different size/shape. It all works in the end!
As I mentioned, the sketch line is a guide as when I try to stick right to the line, I end up with the FMQing being all jiggly and not looking smooth.
You could use any of the quilt marking methods.
Just be sure that you test first to know whether there is any risk to the marks remaining permanent.