The most common and most likely answer to this crossword clue is the 7 letter word UNCROSS
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More clues leading to the result UNCROSS
Buddy explains!

The straight part
We know that "change position" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case change position = uncross.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 UNCROSS mean?
UNCROSS verb- To move something, especially one's arms or legs, from a crossed position.
- To undo the crossing or traversal of.