Maybe a bit of mental stimulation might help? Anything involving nose work is ideal for cockers helps them focus and uses up a lot of energy - 15 minutes searching will tire her as much as a long walk. There are lots of training ideas online but you can start by hiding toys in fairly simple places, under cushions, behind curtains for exmple and then make it more difficult. If she‘ll sit and stay, you can hold what ever toy/object it is, let her sniff it and tell her to wait while you hide it, you can then release her to go and search (or you cann get someone to hold her or hide it in another room. (You can eventually introduce different toys so that she learns the names ) Or you can lay a trail of treats and let her sniff them out.
A simple cardboard box full of screwed up newspaper containing a few treats will keep her happy for a while, or collect some empty toilet rolls, stand them upright in a shoe box and put a few treats inside some of them....
Can’t guarantee that it will solve the chewing problem altogether but if it is caused by boredom or anxiety then any sort of occupation that distracts, encourages concentration and builds self confidence should help - but be careful to make sure that the exercises/games aren’t too difficult, its important that she‘s succesful otherwise she‘ll just get frustrated and bored, which is ofcourse contra productive.
My dog loves nose work and its great for bad weather days (and lockdowns
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It‘d be interesting to learn how she develops, do keep us posted please!
Best of luck!