Size 8 is too small for trannies and too big for most women - that could be an issue.
I had some boots I thought were lovely. DH hid them and I asked why and he told me they were vile. I asked a few friends and they confirmed they assumed I had been given them and were wearing them out of guilt or something
It's not the size, I've sold quite a few things in size 8/42 and they go really well. It's the boots tbh, they're not that nice. Also I think people search by brand, so unbranded stuff will get far fewer hits. I sold a pair of DUO boots worn only a few times for £50 a couple of weeks ago.
Also I tend to start at 0.99, I think overall you get more interest and a better final price, plus you don't pay listing fees.