Hi ReginaldDuck,
If the customer is the importer of the goods over the value of £135 then you are not making any taxable supplies.
If you sell goods under £135 through a marketplace and the goods are sent directly from Gibraltar then you are not making taxable supplies.
Therefore there will be no requirement to register for VAT in these cases.
If the goods of any value are in the UK when sold and these goods are being sold via a marketplace then you will be making a deemed zero rated supply to the marketplace.
These zero rated deemed supplies are taxable supplies and will require you to register for VAT.
However you can apply for an exemption to reistration if you supplies are all or mostly zero rated.
Please see the guidance below, specifically section 3.11
3.11 When you might be exempt from registration
You may want to consider registration , however, if you import goods in to the UK before they are sold as it will allow you to recover the import VAT as input tax on your VAT return.
Thank you.
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