5.  So far as a function under [F1retained EU law], or to which section 53(2)(a) of the 1998 Act applies, is exercisable by a Minister of the Crown–U.K.

(a)in relation to fishing or aquaculture in the Scottish zone, or

(b)in relation to fishing outside that zone by Scottish fishing boats,

(c)in relation to any fish or aquaculture organisation applying for recognition as a producers' Organisation, or recognised as such in accordance with [F1retained EU law], whose area covered by the application for recognition, in so far as within the United Kingdom or British fishery limits, is wholly or mainly within Scotland or the Scottish zone,

it may be exercised separately.