I assume you're looking for the right way to tweak 'sparring' in English. I have come across this very often when translating material for management development seminars and books on entrepreneuship and the Danes love the word sparring. I feel that 'constructive feedback' best conveys what is meant here. Or something like 'udveksling af ideer til gensidig inspiration' but that's more on a personal level rather than a website, e.g., amongst colleagues or at a job performance interview, etc. Hope this helps :)