I found an old article talking about the difficulty getting it published in Europe and why it was farmed out to THQ. Here’s a statement from Nintendo explaining why:
“Nintendo of Europe is pleased to confirm that Conker’s Bad Fur Day will be released by THQ International across Europe for the Nintendo 64. Nintendo of Europe decided against publishing the game following a full commercial appraisal. It is the policy of Nintendo of Europe to translate our games into the native language of the region where it will be released and due to its text-heavy content, the cost of localising Conker’s Bad Fur Day would not be commercially viable. Nintendo is pleased that the English-language version of Conker’s Bad Fur Day will be available – through THQ – for N64 fans across Europe.”
https://www.ign.com/articles/2001/03/03/thq-conkers-europe
by FireFlareon