Speaker for nearfield listening?

You might audition speakers that have a single driver, like the Audience The One. They resolve beautifully at close distances.

Speakers from Harbeth and Spendor that are designed as nearfield monitors are also a good choice.

Finally, I had a pair of Totem Arros that I listened to from about six feet distance, and their imaging was spectacular. This speaker is known for its ability to create a soundstage in a small environment.

Second the Harbeth P3ESR. Not such a fan in the past but they have upped their game and are far more dynamic and resolve better. No longer that laid back British sound.

Depending on your amp I would say try the KEF Q300 bookshelves. With a Jolida JD-502P tube amp with the KEF Q300 speakers I found nearfield listening very enjoyable. When I swapped out the Jolida for a Hafler 9505 solid state amp and the music got really forward but could still be loud and clear from a farther distance.

My Shelby+Kroll Nano Monitors and dual Woofer Monitors are crazy good in the near field. For your listening at 6' a single Woofer Monitor would be sufficient. The imaging of the S/K is spooky real.
When the S/K Nano Monitors were first delivered I had them set up on a counter top and couldn't believe what I was hearing. Superior height,depth, and width to the sound stage, with perfect tonal balance. When the stands showed up I put them about 3' off the front wall and 8' apart. From my chair they sounded exquisite, but here's the cool part, when I would get up to turn off the gear (rack in middle of front wall and against it) I would stand about a foot in front of the speaker plane and still enjoy a 3D sound experience! Feels like you can reach over and smack a cymbal.
I first heard the S/K Nano Monitors and Woofer Monitor at a guys house and were about 6' apart and sounded great there too.
Good luck

I agree with Wolf, and would add the Thiel MCS for consideration.