May I know how to make the gradient color looks more natural after filling by the content-awareness on the left?
I tried to use a Stamp tool, but it does not work as expected. :(
You can use the Patch tool for such areas.
1) Select the patch tool from the tools panel.
2) Make the selection of the area you wish to edit. (Make sure to go with small areas as it will lead to a better result.)
3) Drag the selected area to its left or right to patch and heal the selected area.
4) Repeat these steps for the remaining parts and you will get the desired result as shown below.
** COMPARISION:**
Result
A way to avoid needing the answer at all, don't make that line in the first place...
Don't feather the selection edge before using content-aware fill, especially on such an 'easy' fill as that & it won't make that line at all.
Exaggerated feathering...
No feathering...