ACROSS
 1. "OVERSEES" = OVERSEAS <abroad>
 6. <talks> SUMMIT = SUM + MIT
 9. (FOR ME) + D = FORMED <made>
10. <reception> ANTEROOM = ←MOOR + ETNA←
11. <depiction of farmers> AMERICAN GOTHIC = (MANIOC + AGRITECH)*
13. S + ALT = SALT <mineral>
15. <merciless> INEXORABLE = (BARON + EXILE)*
17. <they believe> PANTHEISTS = PANTS outside HEIST
19. LAS S_ = LASS <child>
21. <she's written> MARGARET ATWOOD = ←A TERAGRAM← TWO O D
23. <strange> PECULIAR = P ECU + LIAR
24. <bound> GAMBOL = "GAMBLE"
26. <deceives> BLUFFS <banks>
27. <discouraged> DETERRED = DET + ERRED

DOWN
 2. <sound of vehicle> VROOM = VR ←OOM←
 3. R U M = RUM <Captain Morgan?>
 4. DOC R inside E NINE = ENDOCRINE <producing hormones>
 5. <people led by Tecumseh> SHAWNEE = →"NOR SHE"←
 6. <brawl> SET-TO = SETT O
 7. MARS HM + ALLOW = MARSHMALLOW <sweet>
 8. E inside OSSICLES* = ISOSCELES <with mirror symmetry>
12. O TA TORC inside RUFF = ROTATOR CUFF <joint support>
14. ALL outside MARBLE* = ALARM BELL <siren?>
16. <offensive> ONSLAUGHT = (.o)ON'S LAUGH T(a.)
18. S NEE RED = SNEERED <smiled scornfully>
21. ARES outside I = ARIES <constellation>
22. <toxic gas> OZONE = O ZONE
25. <space station> MIR = ←RIM←