Will my scar be noticeable with a 4 guard haircut? I'm almost 7 weeks out from an FUT procedure. (Photos)

Give your donor area time to grow out. It may take a couple months to fully grow out. In my opinion you will be able to cut your hair with less than a 4 guard.

It will take time for your donor area closure to be fully healed.  The tension of the closure can be traumatic to surrounding hair and can cause some hair to shed temporarily.  Pinkness can last 4 - 8 weeks but should go away completely.  As the donor strip is shaved prior to removing, when closed there still may be be some shaved hair on the closed edges as well.  If the donor is closed at the right tension and with proper technique ultimately a hairline scar should form that typically should not visible with hair at a #2 - #4 clip.   Every patient varies in terms of donor density and how there skin heals so how short one's hair can be without revealing the scar fluxuates.  I expect you will be more comfortable with your appearance about 4-5 months post-op.
Dr. D

I would give at least 6 or 8 months before assessing the healing of your scar and the visibility with a short haircut. You may have some donor site shock loss or the scar may just be still healing!If it is visible after this period of time, you always have the option to put FUE into the scar or use SMP to hide the scar,Dr. Robert Jones

It appears that your hair was cut without thought to your scar. Let your hair grow just a little longer with the object to camouphlage the scar and then decide.

The scar is detectable because the hair around the scar is short.  I am not seeing the scar to give an opinion but wait it out and balance the hair cut and then reassess your situation