Following issues:
Caught Fish do not show up in Inventory and are replaced by Rations and Leather.
Hunted Animals do not drop any hunting Items such as hides, bones or antlers etc.. only leather
I killed the legendary Moose but i don't get any Rewards or Trophies at the Hunting Building.
Hello there @bahutsauvage!
As shared by @RustyMelvin, these features are working as intended as Vinland is a unique location. You won't be able to collect any animal products (besides leather and rations) from hunting or fishing. Additionally, you cannot bring O Yan Do' Ne's head back with you to Ravensthorpe. You should get a large amount of leather and two skill points for your victory, though!
Thanks for sharing your feedback about having O Yan Do' Ne and the Black Stout available to be mounted in the longhouse, @ETSubmariner. I'll pass your feedback along to the development team for further consideration. If these legendary animals are to become available as longhouse trophies, this information will be shared via patch notes within the News & Announcements forum.
Thanks! 
Hello @etsubmariner,
Thank you for your feedback! I'll pas it along to the team 
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