While it seems 'legal', cannabis and its user ready 'drugs' products are still illegal in the Netherlands.
So there is no 'bought legally' in the Netherlands for any product that can get you high.
There are some weed flavoured items that do not contain the active parts, them you can take home.
For the rest, it is as (il)legal to buy it at home.
The airports are all in 'no tolerance' zones, and as far as I remember, so are the ferries. There is a rather high chance on being selected for further checks when arriving from Amsterdam, more so when traveling as a group of young adults, mostly male.
*Note, this is a slightly stronger point of view than many people claim is legal for use of cannabis within the Netherlands, but that is more opinion than fact when considering export.
Cannabis and the products made of it are 'gedoogd' which translates to 'tolerated when rules are followed but still illegal.' Some people here take the stance that they are not illegal as they are tolerated, I, and many with me, keep to what my (Dutch) gouvernment tells me, they are still illegal within the Netherlands.