Across:
8 Realise (ATTAIN) a (A-) temperature (-T-) ain’t (aint) problematic (= anagram indicator) (aint = -TAIN) (ATTAIN),
9 One of the twelve Olympians (POSEIDON) is model (POSE-) for one (-I-) gangster (-DON) (POSEIDON),
10 Sounds like (= homophone indicator) Count’s (‘adds’ = ‘ADZE’) for the chop (axe-type tool = ADZE),
11 This will have you going in circles? (CONCENTRIC) Trick (CON-) by rugby player (centre) – briefly (e) (‘centre’ without ‘e’ = -CENTR-), the one (-I-) caught (-C)! (CONCENTRIC),
12 The Japanese drama (Japanese theatre / drama = KABUKI) is fairly kind (fairly/half of ‘KInd’ = K-I) about a (-A-) brilliant leader (‘Brilliant’ leader = -B-) and neighbour (-UK-) (KABUKI),
14 Designed (= anagram indicator) denim cap (denim cap = PANDEMIC) that could be a killer if it goes global (PANDEMIC),
15 Daydreaming (ESCAPE MECHANISM) of 21 down (‘escape’ = ESCAPE) with soup (= anagram indicator), mash, mince (mash, mince = MECHANISM) (ESCAPE MECHANISM),
18 Freudian slip with no puns (‘Freudian slip’ with no ‘puns’ = frediali = AIRFIELD) produced by JFK, the one in New York? (JFK airport in New York = AIRFIELD),
20 Take sip from petri dish (take ‘sip’ from ‘petri dish’ = dtridh = DITHER)? Oh, I’m not sure about that! (DITHER),
22 Criminal (CON-) at firm (-CO-) is taken to court (-CT-) and is charged (-ION) (CONCOCTION) with a mixture that came from the drug dealer (CONCOCTION),
24 One of those forward types complain getting this from defensive type (forward type + defensive type = footballers / KICK), to boot (KICK),
25 Shooting star (METEOR-) in charge (-IC) (METEORIC) of Fast Track that relates to The Rising (METEORIC),
26 What the hacks are looking for (SCOOPS) are not freely available in the parlours (SCOOPS in ice cream parlours).
Down:
1 Nine released from East Indian (‘nine’ released from ‘East Indian’ = astdia = STADIA) venues (STADIA),
2 Advertise leaving out tired (‘advertise’ leaving out ‘tired’ = avse = VASE) jar of flowers (VASE),
3 Fashionable (IN-) mobile (-ACTIVE) (INACTIVE) is not in service (INACTIVE),
4 Quick trip (SPIN) around Spanish Main (around ‘SPanish maIN’ = SPIN),
5 Won’t find it in train set (‘it’ missing from ‘train set’ = ranset = ASTERN) or at the back of the ship (ASTERN),
6 Form union (TIE THE KNOT) in Windsor (Windsor TIE) for most of (m) them (them) (‘them’ without ‘m’ = THE) from 24 down (‘knot’ = KNOT) (TIE THE KNOT),
7 Spoilt (spoilt = POLIT-S)? Oddly (= anagram indicator) me (-I-) – first child (first ‘Child’ = -C-) inside (POLITICS) charged with doing the housework! (charged with doing The House work = POLITICS),
13 Modest (UNAFFECTED) organisation (United Nations = UN-) has a (-A-) party (Fianna Fáil = -FF-), etc. (etc), organised (= anagram indicator) (etc = -ECT-), for writer (-ED) (UNAFFECTED),
14 Make an emotional appeal (PLEAD) for police (P-) escort (-LEAD) (PLEAD),
16 VIP loser (VIP loser) lost (= anagram indicator) (VIP loser = SLIPOVER) something to wear (SLIPOVER),
17 That man (HE-) is (-IS-) following (= position indicator) Mafia leader (-DON-) on motorway (-M) (HEDONISM) out of the pursuit of pleasure (HEDONISM),
19 It’s just more (ENCORE) of what the fans asked for in the end (ENCORE),
21 Flight (ESCAPE) showing off (= anagram indicator) space (space = ESCAP-) age at the foundation (‘agE’ at the foundation = -E) (ESCAPE),
23 Some of the porcelain china (contents of ‘porcelaIN China’ = INCH) produced by the smallest town in Wexford? (INCH),
24 Garda – the one associated with Hitch (‘garda hitch’ climbing KNOT) – taken in by Preston King (taken in by ‘presTON King’ = tonk) going all the way back (= reverse indicator) (tonk = KNOT).