Best treatment to fade a year old white scar

Give it more time. Unless the scar is contracted or distorting the skin, then it needs to be revised.

If it is wide enough then revision can be done. If it is just the whitish colour of a linear scar then in my hands a skin tattoo (micro pigmentation) will be more than enough to equalise the skin tone with 1-2 sessions. I hope this was helpful enough. Thank you