According to a report from brickfanatics, BrickLink is attempting to implement a solution that will make the platform responsible for the collection of VAT for purchases under £135, rather than the seller.
Currently, sellers in the EU are responsible for paying sales tax for their non-EU residing buyers when purchases are over £15. Those sellers are expected to register and pay the HMRC what they owe. However, as spoken about previously it looks like brickLink will be responsible for VAT on all purchases under £135 as per UK government guidance;
“The new arrangements will also involve the abolition of Low Value Consignment Relief, which relieves import VAT on consignments of goods valued at £15 or less.
Online marketplaces (OMPs), where they are involved in facilitating the sale, will be responsible for collecting and accounting for the VAT.”
– gov.uk
BrickLink seems to be doing what they can to ensure this after confirming that they are registered as a UK marketplace. They have however also made it clear that they are still working on implementing the VAT collection solution. If you are an EU seller currently shipping goods to the UK it might still be a good idea to register with the HMRC to avoid any issues whilst said solution is being sorted out.