Subsitute Moss Stitch

I’ve got a pattern for a simple cardi which has a simple edge of 8 rows of moss stitch on the bottom, edge of cuffs and up the front on both sides. I wondered if i could do 8 rows of garter stitch instead of moss?

Yes, though it may turn out a bit wider and shorter, so you may have to compensate for the number of stitches and rows if you need it to be the same measurement.