One legality covering alot of goods that are bought in from outside the eu is CE type approval. On goods that require type approval, if they dont have the sticker, it is illegal to sell them new here. I dont know how this covers outboards, but some of the machinery that i sell at work is not CE so we have difficulty in selling it new legally. Even if you see it already for sale here with the CE approval sticker, it doesnt mean that the grey import is CE.
AS for breaking any other laws, i think realistically it would be a civil issue between the manufacturer and the seller only if you were selling them and calling yourself an authorised dealer. Remember that it may be cheap to import one for yourself at that price, and avoid the middleman, when you do it as a business and resell them with a sensible mark-up, it probably isnt a goldmine after all!
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