For a panel fe regression where the IV and DV have both been log-transformed, I would like to know how I can use the margins command to identify the marginal effect of the original (non-log transformed) IV on the original (non-log transformed) DV. To give a very simple example, lets take the IV and DV to be x and y. The regression function is:

xtreg ln_y ln_x, fe

margins, ln_x will give the marginal impact of ln_x on ln_y. However, I would like to find the marginal impact of x on y. Is there anyway to use the "expression" option with margins to obtain this? Thank you.