Changes M&S trousers for friend returning legwear (13)

I believe the answer is:

metamorphoses

I'm a little stuck... Click here to teach me more about this clue!

'changes' is the definition.
(metamorphosis is a kind of change)

'ms trousers for friend returning legwear' is the wordplay.
I cannot really see how this works, but
'legwear' could be 'hose' (I've seen this in another clue) and 'hose' is found in the answer.
This explanation may well be incorrect...

Can you help me to learn more?

(Another definition for metamorphoses that I've seen is " Complete changes".)

I've seen this clue in The Telegraph.

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