Solution to 2D has been deliberately left unsolved and is to be answered only by a non-regular / novice commenter, with proper annotation. Those who have answered earlier in the week, please give others a chance.
Open for anyone to answer, if not solved by 1 PM.
NICE PAIN
ACROSS
1 Workers laid off? Tad fishy (3,5) DAY SHIFT*
6 Ignore outrageous abyss next to eastern edge of camp (4,2) PASS BY {ABYSS}*<=>{camP}
9 The two of us texted for dinner options? (4) MENU (~ ME 'N U}
10 Bali trek is tailor-made for rugged two-wheelers (5,5) TRAIL BIKES*
11 Straight storyteller capturing fringes of lesbian lore (6) LINEAR {LI{l...aN}{lorE}AR}
12 Detective probing American dude's murder (8) HOMICIDE {HOMI{CID}E}
15 Gussalufz accompanying gangster for lunch? (4) MEAL {ME}{AL}
17 Unchanged support after leader's ouster (2,2) AS IS bASIS
18 Son, sleep long on ship, for energy (10) SNAPPINESS {S}{NAP}{PINE}{SS}
20 Antelope ecosystem buckled after all-round grazing (8) STEMBUCK [T] Couldn't find this spelling anywhere
24 Young abstainers, taking off clothes, give up and loudly dance on ecstasy (4,2,4) BAND OF HOPE {aBANDOn}{F}{HOP}{E}
26 Head priest dined (4) PATE {Pr...t}{ATE}
27 Party offering to preserve copy (6) CANAPE {CAN}{APE}
DOWN
2 Rampant tantrum and rage in resort, for starters (9) A?E?I?I?S ()
3 A brute, lacking limits in behaviour, goes after small fry (5) SAUTE {A}{brUTE}<=>{S}
4 Acting in period features (international) (7) INTERIM {IN TER{I}M}
5 Half of trailer cut for interval (3) TEA TEAser
6 European with microphone, offering contentious argument (7) POLEMIC {POLE}{MIC}
7 Train workers to crawl through hairy mews with caution, ultimately (9) SWITCHMEN {ITCH}* in {MEWS*}{c...oN}
8 Badaam at first, then take paratha? (5) BREAD {Ba...m}{READ}
12 Ah, turning pitch, where some bowlers might be rested (7) HATRACK {AH<=}{TRACK}
14 Indian state in upheaval around healthcare staff cut: news outlets (4,5) MASS MEDIA {ASSAM<=} over {MEDIcs}
16 Like the middle of hamburger slices—seasoned and battered (9) ASSAULTED {AS}{SA{h..bUr..r}LTED}
19 A fine, extremely encyclopedic Essence of Anatomy textbook (7) PERFECT {PER}{F}{En...iC}{anaTomy}
21 ChatGPT, possibly possessed by craftiness, goes overboard; this might go over one's head (5) TIARA {AR{AI}T}<=
23 Road-racing? A pedestrian crossing sides stared in shock (5) GAPED [T]
Reference List
Gangster = AL(Capone), Son = S, Ship = SS, Loudly = F, Ecstasy = E, Small = S, Right = R, Fine = F


