Same here. As others have said, you really have to look to see any issues. Don't forget: we are our own worst critics and who sees it at 50 feet on a galloping horse. :)

I only see a problem because you mentioned it.

Winnie Fleming covers this topic in her Finishing Techniques (or a title real close to that) class on craftsy. She explains in detail how to cut the border fabrics (and why). It is a class I have referred to for other topics and I plan to use her method when I get to work with a miter.

Good luck - your block is beautiful.

Beautiful block.

I do not think fabric is printed exact enough to get it closer to perfect than you already have it . Looks great

Don't have an answer for you but that block is stunning.
I love it.

It took me a minute to see the one miter. If I weren't putting it in a show, I wouldn't bother to fix it... but since you asked:

I'm sure you've already watched this video: https://www.youtube.com/watch?v=cNPOkcyrMSg

Jinny says the block doesn't need to be perfectly square. The trick is to line up the center of your border strip with the exact center of the block & then mark the 1/4" points on both your border & block. It looks like you may have needed to ease in a bit of the block in that section in order for your points to match up.

I really had to study the picture to figure out what you were talking about. I think Bearisgray has the right idea.

A demo at our guild meeting for mitering corners of a quilt might work. You sew on your borders, stop exactly 1/4 inch from the corner. Then you iron your your miter and make sure your seams line up. Place a piece of painters tape over it to hold it all in place. Then you flip it over and sew exactly on your crease. Hope this makes sense.
Your block is gorgeous.

How can you find a 'trick' when you've done so excellently!? For the record, anyone who measures or critiques lines not matching, doesn't deserve my works of art!