Across:
1 Strange (FOREIGN) coming from 5 down (‘legion’ = LEGION) (FOREIGN LEGION) in overseas unit with a number of nationalities (FOREIGN LEGION),
10 No ads in El Salvador (no ‘ads’ in ‘El Salvador’ = ellvaor = OVERALL) by and large (OVERALL),
11 Scientist associated with Sky (GALILEO) had problems with The Sun’s direction perhaps (GALILEO),
12 In Simplex, a mercurial (in ‘simplex a mercurial’ = EXAM) type of academic challenge (EXAM),
13 Characters in name of edition (characters in the ‘name of edition’ = eofed = DEFOE) reviewed (= reversal indicator) by author synonymous with Friday (Daniel DEFOE author synonymous with Man Friday),
15 Central Massif re-evaluated (central ‘Massif re-evaluated’ = FREE) at no cost (FREE),
17 Gangster (DON) and doorman missing Roma (‘doorman’ missing ‘Roma’ = don = DON),
19 Fishy type (GAR-) of starters with lobsters in ceviche (starters with ‘lobsters in ceviche’ = -LIC) (GARLIC) that leaves a pungent aroma on the breath (GARLIC),
21 Odd (= anagram indicator) menu (menu = NU-ME-) includes tea (-T-) with little measure (gram = -G) (NUTMEG) of spice (NUTMEG),
22 You’ll get this from good wine (NOSE-) and wine in box (-BAG in box) (NOSEBAG) – the type you could give to an Arabian (NOSEBAG for Arabian/horse),
23 Bitterness (ENMITY) of the last of the sage (last of the ‘sage’ = E-) and wild (= anagram indicator) mint (mint = -NMIT) from yard (Y) (ENMITY),
25 Paint a (paint a = PATINA) model (= anagram indicator) from glossy film (gloss/sheen on wood = PATINA),
27 Genealogist dismisses toenails (‘genealogist’ cuts ‘toenails’ = geg = EGG) found in Mayo (EGG is in “mayo”),
29 Inkling (IDEA) of what’s in splendid eatery (what’s in ‘splendid eatery’ = IDEA),
30 Mailer is missing from All-American (‘Mailer’ is missing from ‘All-American’ = alcan = CANAL) passage synonymous with Venice, for one (CANAL),
31 Endless (h) St Patrick’s Day Parade? (‘march’ without ‘h’ = MARC) That’s the spirit! (MARC spirit made from pressed grapes),
34 Leave behind (OUTGROW) great (-G-) trouble (-ROW) on holiday (OUT-), for starters (= positional indicator) (OUTGROW),
35 Note in a (note in a = ETONIAN) novel (= anagram indicator) by one who got an education in England (ETONIAN),
36 What The Tourists are doing (FOREIGN TRAVEL) is strange (FOREIGN) with first-time (first ‘time’ = T-) composer (-RAVEL) (FOREIGN TRAVEL).
Down:
2 Kind of festival (OPEN-AIR festival) of opera in (opera in = OPEN AIR) resort? (re-sort/sort it out again = anagram indicator),
3 Model a nostalgic bit (‘model a nostalgic’ bit = ELAN) of style (ELAN),
4 Government (G-) lied (lied = -IL-ED) awfully (= anagram indicator) about top departmental (top ‘departmental’ = -D-) (GILDED) cover-up (cover up with gold = GILDED),
5 Vast numbers (LEGION) on both sides of legal profession (on both sides of ‘legal profession’ = LEGION),
6 Bottled gas, at best, missing (‘bottled gas’ ‘at best’ missing / without ‘at best’ = oldg = GOLD) the precious stuff (GOLD),
7 Drunk (= anagram indicator) old rum I (old rum I = OIL DRUM) produced in crude container (OIL DRUM),
8 Journalist working overseas (FOREIGN EDITOR) is not from this country (FOREIGN) – that’s one for the books (EDITOR) (FOREIGN EDITOR),
9 Presumably heard at the UN (FOREIGN ACCENT) from unfamiliar type, in a manner of speaking (FOREIGN ACCENT),
14 It’s exotic (FOREIGN) to all sides today (FOREIGN on all sides of today’s grid),
16 Thins (thins = HINTS) soup (= anagram indicator) and gives a taste of what’s to come (HINTS),
18 Poser leaves sour grapes (‘poser’ leaves ‘sour grapes’ = ugras = SUGAR) for something sweet (SUGAR),
20 Shy type (COY) limps out of Olympics (‘limps’ out of ‘Olympics’ = oyc = COY),
21 Some abandon a programme (some ‘abandon a programme’ = NAP) for the rest of the afternoon (NAP),
24 Expert (MAESTRO) team (team = MAE-T) comes back (= reversal indicator) across south (-S-) Romania (RO = -RO) (MAESTRO),
26 Think (IMAGINE) of a Gemini (a Gemini = IMAGINE) freaking out (= anagram indicator),
27 Listen secretly (EARWIG), going on ahead (going on a head = -WIG) after (= position indicator) a sound type (EAR-) (EARWIG),
28 Sounds like (= homophone indicator) hard luck (“hard luck” = “hard look” = GAZE AT) for peer (GAZE AT),
32 Teachers have no cash (‘teachers’ have no ‘cash’ = teer = TREE) for the children’s playhouse (TREE),
33 Drink (SODA) from bottle in Valparaíso dairy (bottle in ‘Valparaíso dairy’ = SODA).