Butter from Netherlands and Austria essentially eliminated by Brexit, unfortunately (4)
I believe the answer is:
ibex
'netherlands and austria essentially eliminated by brexit unfortunately' is the definition.
I can't judge whether this defines the answer.
'butter from' is the wordplay.
'butter' becomes 'ib' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'from' becomes 'ex' ('from' in Latin).
'ib'+'ex'='IBEX'
Can you help me to learn more?
(Other definitions for ibex that I've seen before include "Mountain-goat" , "one used to high living" , "Pyrenean mountain goat" , "Large-horned wild goat" , "Sure-footed climber" .)