How about using something with a flange and fitting it from inside the shoe so that the flange sits directly underneath the insole. A Tee- nut without the prongs would do the job.
I can't think past that being a very effective thermal bridge.
@drøn started
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How about using something with a flange and fitting it from inside the shoe so that the flange sits directly underneath the insole. A Tee- nut without the prongs would do the job.