Categories of influencer - surely you are either an influencer (paid to promote a product) or an enthusiast, extolling the virtues of something you like ? Collaboration would mean “working with” and I not sure that’s something we are seeing here - these are critics / wine press.
On disclosure - So Chris Kissack (the winedoctor.com the most transparanet critic - he posts his “freebies” every year…great reading!) is invited to a TWS press tasting and he posts a picture of a sample he tasted…what should he put on his post ?
He hasn’t been paid to attend - in fact he paid his own travel. He was given a small sample to taste on the hope that he will write about it - is that quid pro quo or is he working pro bono ? certainly nothing to disclose to HMRC as no payment has been made for the “copy”