The most common and most likely answer to this crossword clue is the 6 letter word TOOLED
I've seen this crossword clue in The Sunday Telegraph
T
O
O
L
E
D
More clues leading to the result TOOLED
Buddy explains!

The straight part
We know that "impressed with design" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case impressed with design = tooled.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.
What does TOOLED mean?
TOOLED verb- To work on or shape with tools, e.g., hand-tooled leather.
- To equip with tools.
- To work very hard.
- To put down another person (possibly in a subtle, hidden way), and in that way to use him or her to meet a goal.
- To intentionally attack the ball so that it deflects off a blocker out of bounds.
- To drive (a coach or other vehicle).
- To carry or convey in a coach or other vehicle.
- To travel in a vehicle; to ride or drive.
- Worked with a tool.
- Impressed with an ornamental design.