Across:
1 Local swallowed (local 'swallowed' = DOWNED) the last section of 14 across (last 'dressing down' = DOWN-) by writer (-ED) (DOWNED),
4 The wings (OFFSTAGE) of duck (O-) for party (Fianna Fáil = -FF-) in the abbey (-STAGE) (OFFSTAGE),
9 What you will (ESTATE) find in Spain (E-) and Portugal for example (-STATE)? (ESTATE),
10 It’s a great sacrifice for the old Greeks (HECATOMB), as each (each = HECA-) suspect (= anagram indicator) comes to grave ending perhaps (-TOMB) (HECATOMB),
12 Celebrities tend to go over it (RED CARPET) at the end of 1 down (end of ‘deep reds’ = reds) endlessly (s) (‘reds’ without ‘s’ = RED) and get reprimand (CARPET) (RED CARPET),
13 Flips over (flips/leans over = LISTS) composer (Liszt) on the radio (= homophone indicator) (‘Liszt’ = ‘list’ = LIST-) associated with first symphony (first ‘Symphony’ = -S) (LISTS),
14 Lecture (DRESSING DOWN) 26 across (‘dressing’ = DRESSING) in Northern Ireland (DOWN) (DRESSING DOWN)
18 Opens 14 across (opens ‘dressing down’ = DRESSING) and most of those in 23 down (most ‘gowns’ = GOWN) (DRESSING GOWN) – the type that’s tailored for those cold mornings (DRESSING GOWN),
21 Canoe (canoe) out of place (= anagram indicator) (canoe = OCEAN) in a large body of water (OCEAN),
22 Presumably, they get their marching orders in July (ORANGEMEN) from old (O-) crazy (= anagram indicator) green man? (green man = -RANGEMEN) (ORANGEMEN),
24 Turns up (= reversal indicator) broadcast (air = -RIA), etc. (etc = -CTE-), on an old boat (able-bodied seaman = ab = BA-) (BACTERIA) with bugs (BACTERIA),
25 Weekend (‘weeK’ end letter = K-) bar for magicians (wand) is not finished (d) (‘wand’ without ‘d’ = -WAN-) by wizard at The Centre (‘wiZArd’ at the centre = -ZA) (KWANZA) with Angolan capital (Angolan capital/ money = KWANZA),
26 Sauce (DRESSING) for starter in 18 across (starter in ‘dressing gown’ = DRESSING),
27 Jockey (= anagram indicator) a horse (a horse = ASHORE) on dry ground (ASHORE).
Down:
1 Thought provoking (DEEP) revolutionaries (REDS) (DEEP REDS) drunk in Bordeaux (wine), for example (DEEP REDS),
2 Did an about turn (WITHDREW) as funny woman (WIT-) on drugs (heroin = -H-) painted a picture (-DREW) (WITHDREW),
3 Divorcee (EX-) picks up (= reverse indicator) crafty type (art = -TRA) (EXTRA) of actor – the type who has nothing to say for himself! (an EXTRA),
5 Holds the top job working overseas (FLEET ADMIRAL) in a position that provides time off in 27 across (FLEET ADMIRAL has time off ‘ashore’),
6 Barman (Senior Counsel = SC-) met partner in The Troubles (partner in the troubles/war = -ALLY-) with the wife and girlfriend (‘Wife And Girlfriend’ = -WAG) (SCALLYWAG) of scoundrel? (SCALLYWAG),
7 Go on a pub crawl (carouse), heading off (c) (‘carouse’ without ‘c’ = AROUSE) with Foster, evoking strong emotions? (AROUSE),
8 Yours truly (me) upset (= reverse indicator) (me = EM-) with order about (-BOSS) (EMBOSS) Imprint, so it stands out (EMBOSS),
11 In a manner of speaking (SPANISH), initial interruption (initial ‘Interruption’ = -I-) in two broadcasts (on + on = ON-ON) (SPANISH ONION) is a product of Basque plot presumably (SPANISH ONION product of Basque/Spanish plot/allotment presumably),
15 Crafty type (SS = S-S) welcomes newspaperman (-PRINTER-) (SPRINTERS) and those on the fast track (SPRINTERS),
16 Order (COMMAND-) from Ring (-O) (COMMANDO) – the one sent on The Missions (COMMANDO),
17 Turn a blind eye without Beryl (‘turn a blind eye’ without ‘Beryl’ = tunainde = INUNDATE) Flood (flood/overwhelm = INUNDATE),
19 Bride-to-be has no tie (‘bride-to-be’ has no ‘tie’ = brdobe = ROBBED) or stole? (ROBBED),
20 Save (RESCUE) Earl (-E) and Charlie (-C-) taken in by drug taker (user) giving everything up (= reverse all indicator) (user = RES-U-) (RESCUE),
23 The odd good wine (the odd letters in ‘GoOd WiNe’ = GOWN-) is served first (‘Served’ first = -S) (GOWNS) for those going to the ball (GOWNS).