Valid on both sides of the English Channel.

- expect increased postage tariffs between UK and EU because of UK jump to "third country" category.

- expect increased paperwork (customs documents, invoices) for sending items between EU and UK.

- expect VAT and customs duties to be added from certain amounts on. 

- expect longer delivery times  (with delays in customs).

- expect UK standards items no longer being accepted in EU.

Some of these regardless of any (no-) deal. Combined with the Global Shipping folly which costs your foreign customers on average 40% more for shipping the future is not bright for foreign sales.