Across
1 T and P (the initial letters of Tribal People) when sounded out = teepee aka wigwam
4 Edge (limit) + ways (means) = edgeways; could you get a word in edgeways when talking with a chatterbox
9 Lent (fast) + IL (forty nine in roman numerals) = Lentil = a pulse (vegetable)
10 Anagram (get knotted) of “to twerps” = Westport
12 Anagram (made up) of “claim four” = forumlaic = unoriginal (conventional etc)
13 Linda contained in dubLIN DAilies
14 Walk (constitutional) and talk (address as in speech) interrupted by i.e. (that is) twice = walkie talkie = communicator
18 A gents (place to go - urinate) after secret (underground) = secret agents = spooks
21 Octet (eight things) found in even letters of tOmCaTs EaT
22 Anagram (elaborate) of “rich roses” = Crossheir who produced a cryptic crossword in the IT (here) every day except Sunday
24 Check (stop) + cock (tilt as in cock your head to one side) = stopcock used to cut off gas leaks for example
25 Outside letters (skins) of FlorencE, DesenzanO and RavennA = fedora = headgear
26 Preclude = rule out; Pre-clued = already hinted at with ed reversed = preclude
27 Freeze (don’t move) sounds like (picked up) frieze (a form of architectural decoration)
Down
1 Wild (unbroken) + fowl = anagram (damaged) of “flow” = wildfowl, a target for game bird hunters
2 Genera (classes - of animals for example) + LS (central letters of Nelson) = Generals) = commanders
3 First letters (first thing) of After Dinner I Ended Up = Adieu = goodbye
5 Anagram (complex) of “action sealed” = deescalation = reduction in tension
6 Ex (former spouse) + tolling (ringing) = extolling = praising
7 Aunt (your mother’s sister) around mo (a second e.g. I’ll be with you in a mo) = amount = volume
8 Sat (modelled) + rap (mild punishment) = satrap an old Turkish Governor
11 ICA (women’s group) inside an anagram (overturned) of “a dirt cart” = tartaric acid = used in some foods
15 I + dent (undermine as in I put a dent in her ambitions) + i cal (one calorie)
16 Rough calculations are often on the back of an envelope
17 Anagram (perhaps) of “mean ruse” =username = a common requirement for online services
19 Top (excellent) + sup (drink) = tops up = refills
20 St (street) + robe (clothing) = strobe = type of light
23 SME (Small & Medium Size enterprise) + a + r (republican) follows (supports) = smear = malign