Across:
8 Graduate (MA= M-A) takes in a (-A-) trail (-LAG-) (MALAGA) from Iberian port (MALAGA),
9 The foreign- (‘the’ foreign/Spanish = EL-) -edited (= anagram indicator) quote (quote = -OQUE-T) about Nationalist leader (‘Nationalist’ leader = -N-) (ELOQUENT) is persuasive, whatever you say (ELOQUENT),
10 Crime bosses (DONS) on the outskirts of Dorset Downs (on the outskirts of ‘DOrset dowNS’ = DONS),
11 Currently working (SWITCHED ON) with mysterious (= anagram indicator) witches (witches = SWITCHE-) and most of those in 10 across (most of ‘dons’ = don = -D ON) (SWITCHED ON),
12 Party (LABOUR Party) for the scientists (LAB-) from old (-O-), old city (-UR) (LABOUR),
14 Fish (LING-) near two islands in the Outer Hebrides (North Uist and South Uist = -UIST) (LINGUIST) with a talker who can yak with everyone overseas (LINGUIST),
15 For instance, first and second (ACADEMIC DEGREES) of 25 across (‘academic’ = ACADEMIC) and 26 across (‘degree’ = DEGREE-) joining society (-S) (ACADEMIC DEGREES),
18 Childish weapon (SNOWBALL) produced by Pole (South Pole = S-) present (-NOW-) at dance (-BALL) (SNOWBALL),
20 Give it time to rest (SETTLE), as there’s no acidity primarily (‘Acidity’ primarily = a) in Washington port (Seattle) (‘seAttle’ without ‘a’ = settle = SETTLE),
22 It’s bloodcurdling (gory = G-ORY) taking in first lecture (first ‘Lecture’ = -L-) for those 18 on course (HOLES) (GLORY HOLES) providing storage spaces for all and sundry (GLORY HOLES),
24 Snare (snare DRUM) what’s at the end of 3 down (end of ‘bass drum’ = DRUM),
25 Cicada (cicada) flying (= anagram indicator) (cicada = ACAD-IC) around yours truly (me) upsets (= reverse indicator) (me = -EM-) (ACADEMIC) one of those in 10 across similarly (ACADEMIC similar to one of the college ‘Dons’),
26 Piece of countryside greenbelt (piece of ‘countrysiDE GREEnbelt’ = DEGREE) comes with a qualification (DEGREE).
Down:
1 Listen in out of sensationalism (‘listen in’ out of ‘sensationalism’ = ssaoam = SAMOSA) for what’s on sale in Indian food market (SAMOSA),
2 Opens 3 down (opens ‘bass drum’ = BASS) for member of barbershop quartet (BASS),
3 Fish (BASS) and duck starter (‘Duck’ starter = D-) served in a pub (-RUM) (BASS DRUM) for musicians – presumably, you can’t say you can’t beat it? (BASS DRUM)
4 Some psychedelic (some ‘psycheDELIc’ = DELI) food market (DELI),
5 Hillary leaves hallucinatory (‘Hillary’ leaves ‘hallucinatory’ = ucnato = TOUCAN) bird with massive bill (TOUCAN),
6 Public official (BUREAUCRAT) with office (BUREAU-) key (music key -C-) opens really accessible toilets (opens ‘Really Accessible Toilets’ = -RAT) (BUREAUCRAT),
7 One backed (one who is backed/endorsed = ENDORSEE) by Leonid to even (‘lEoNiD tO’ even letters = ENDO-) run (-R-) spy (-SEE) (ENDORSEE),
13 Decaying (OLD-) key (music key -E) found on earth (WORLD-) at the back of the house (back of ‘housE’= -E) (OLDE-WORLDE) that’s quaintly outdated (OLDE-WORLDE),
14 Sounds almost like (= almost homophone indicator) it could be of interest to someone on a diet (‘low cal’ = ‘lo cal’ = LOCAL) in the neighbourhood (LOCAL),
16 A local French cop (flic = -FLIC-) follows (= position indicator) criminal (CON-) for time (-T) (CONFLICT) in The Troubles (CONFLICT),
17 Eats (eats) mint (= anagram indicator) (eats = EAST) on salad, for instance (SIDE) (EAST SIDE), with a slice of the big apple? (slice/part of “The Big Apple”/New York = EAST SIDE),
19 Comfortably in (AT HOME) a (A-) big book (tome = -T -OME) about fashion centre (‘fasHion’ centre = H-) (AT HOME),
21 Strange (= anagram indicator) allure (allure = LAUREL) of Hardy’s partner, the joker (LAUREL and Hardy),
23 Run one’s eyes over (look) report (= homophone indicator) (‘look’ = ‘LUCK’) to what’s needed in the betting industry (LUCK),
24 Hounds (DOGS) those arrested by Boris Godunov (those arrested by ‘boriS GODunov’ = sgod), on reflection (= reverse indicator) (sgod = DOGS).