I appreciate that its not FC MOTO but I contacted Louis.de two days ago about this matter ;
"Good Morning
How has BREXIT effected shipping your products to customers in the UK?
Are the British customs charging import duty on your shipments?
Best regards
Craig"
"Dear Mr Craig,
Thank you for your message.
We will take care of the customs fees for you. If you get a letter from customs after purchase, contact us immediately.
If you have any further questions, please do not hesitate to contact us via e-mail or under the telephone number you find below. Thank you in advance.
Best regards
Valerij Metzger"
HTH