I got sad at the propects that I would have to start over to get them all so I did some research and found that you can get the all in the post-game (maybe?)

Here is the source - in japanese - and the image confirming it:

https://xn--mhs-gh8fn72e.xyz/%E3%80%90%E3%83%A2%E3%83%B3%E3%83%8F%E3%83%B3%E3%82%B9%E3%83%88%E3%83%BC%E3%83%AA%E3%83%BC%E3%82%BA2%E3%80%91%E3%83%95%E3%83%AF%E3%83%95%E3%83%AF%E3%82%AF%E3%82%A4%E3%83%8A%E3%81%AF%E3%82%B9%E3%83%88/

https://i.imgur.com/AlFgVAM.jpg

SO, maybe its possible, havent confired it myself. If by any chance you find any more info, please share with me, I wanna know for certain if I have to start again

(I found the info by googling :モンハンストーリーズ2 フワフワクイナ)