I have around 100 Japanese Maples (4 verities- Arakawa, mikawa yatsubusa, Atropurpureum and green dissectum.
The bad news is that any Japanese maple grown from seed is just a Japanese maple.
Cultivars are not stable so you're likely to get a range of different characteristics in the seedlings that germinate. There are so many possible gene combinations in any seedling. Even if some of the seedlings look superficially like the parent variety there will be genetic differences you can't see like height, disease resistance, hardiness to cold or heat, etc that will make them all different from the parent.
Cultivars can only be cloned (graft, cutting, layer, tissue culture) to maintain 100% genetic sameness. No seedling can be the same as any existing cultivar.
The industry already struggles with at least 8 different clones all being sold as 'Atropurpureum' We don't need more different clones masquerading as named cultivars so please don't label or pass any of your seedlings on under the parent name.
To put a more positive slant on it, each and every seedling you grow will be an entirely new and unique cultivar and you get to name them. Just don't use any existing names.
There's nothing wrong with growing see from named cultivars. I enjoy watching the range of different characteristics develop as the seedlings grow and most will be great for bonsai.
Good luck with the seedlings.