A seller on Ebay UK has to wait 180 days to be completely immune from Paypal charge backs, not sure what the deal is with other countries. - can't waite so long so seller must take a bit of risk on him, but we will negotiate about such chargebacks if buyer will win all ebay paypal cases i will return money but again from my experiences if someone not complain about item in first two weeks there should not be a problems.
And getting from GBP Paypal funds into USDT takes extra time and money. - yep. transpact.com can be the option then they can take gbp bank transfers.
I'm interested, more on behalf of someone close who has a small UK ebay store, depends on the item you have and where your located. The postage service you use etc. If your located somewhere like China, fast shipping is important to reduce potential PayPal issues.
If you have a Skype handle, let me know