The new VAT rules will apply to all sales that have a time of supply for VAT purposes of 1 January 2021 or later.
For example, if an order is placed and payment received on 31st December 2020 then the new rules will not apply, even if dispatch and delivery take place after 1 January 2021. Therefore, for imports, the consignment will remain subject to import VAT (unless it is below the Low-Value Consignment Relief threshold of £15) and supply VAT should not be charged. For goods already in the UK at the time of supply, the VAT liability will remain with the seller rather than Wish.
To learn more about the new UK VAT rules for orders after January 1st, 2021 on Wish, please click here.
You can learn more about the UK VAT changes here.