I'm almost 16. Will my jawline become softer if I take hormones or would I need surgery?
I don't really know. It kind if depends how masculine your jaw line is I would think. I know hrt softens your features. It maybe will add some fat but your jaw is bone so I don't think it will actually like change it.
It'll stop the masculinization of the jawbone if it hasn't stopped already.
HRT can soften features by redistributing fat. It will not get rid of bone that has already developed. Preventing masculinized features is why they recommend that young trans folks start on puberty blockers as early as they can, even if they cannot start on HRT right away.