Solution to 13A 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.
ACROSS
1 True, one is missing peace and freedom... (7) RELEASE {REaL}{EASE}
5 ..save partner (7) HUSBAND [DD]
9 Assured criminal flinched as per report (9) CONVINCED {CON}{(~winced)VINCED}
10 Steal primarily expensive, superb costumes (5) ROBES {ROB}{Ex...e}{Su...b}
11 Unfair and imperfect... (7) PARTIAL [DD]
12 ...southern man with everyone wasted half beer becoming meaner (7) SMALLER {S}{M}{ALL}{beER}
13 Dishonest ruler almost eviscerated dynasty (5) S?A?Y (Addendum - {SHAh}{Dy...tY} - See comments)
15 Being old lover is distraught, so to speak (9) EXISTENCE {EX}{IS}{(~tense)TENCE}
17
Cool drink brand with thrust as per report,
sensational (9)
FANTASTIC {FANTA}{(~stick}STIC}
19 Musical work over ages... (5) OPERA {OP}{ERA}
21 ...been around girl in hourly productions (7) ROUGHLY {ROU{G}HLY*}
23 English politician with hesitation takes gold of king (7) EMPEROR {E}{MP}{ER}{OR}
25 Lender in Dayun clearly hoarding (5) UNCLE [T]
26 Paying attention to record, ending with taking out date (9) LISTENING {LIST}{ENdING}
27 Call and speak to... (7) ADDRESS [DD]
28 ...person under doubt on damaging space-suit, the best is missing (7) SUSPECT {SPaCE+SUiT}*
DOWN
1 Instructions are precise? It's all over the place (7) RECIPES*
2 Mad man kills jerk, primarily relating to moon (5) LUNAR {LUNAtic}{Re...g}
3 Sharpness, if boy and girl are swapped can become competence (7) ABILITY A(-g+b)BILITY
4 Once jail department was first-class (9) EXCELLENT {EX}{CELL}{ENT}
5 Conceals husband's papers with evilness heartlessly... (5) HIDES {H}{ID}{Ev...eS}
6 ...with crooked veteran's (lacking empathy primarily) help (7) SERVANT VETeRANS*
7 Vehicle at ambush can't keep quiet carrying a weapon (9) AMBULANCE {AMBUsh}{LANCE}
8 Be worthy of daughter, last wife, get present (7) DESERVE {D}{wifE}{SERVE}
14 Reported that jittery nun in canoe capsized and died (9) ANNOUNCED {NUN+CANOE}*{D}
16 Popular line, leading song proliferates (9) INCREASES {IN}{CREASE}{Song}
17 Restless, four am and lady enters. That's the way (7) FORMULA {FOUR+AM}* over {L}
18 Maybe have ice, finish (7) ACHIEVE*
19 Work on media, harass (7) OPPRESS {OP}{PRESS}
20 Mostly everyone has privilege. OK? (7) ALRIGHT {ALl}{RIGHT}
22 Last deputy speaks when leader is absent, shouts (5) YELLS {d...tY}{tELLS}
24 Go up carrying adult in lift (5) RAISE {R{A}ISE}
Reference List
Southern = S, Man = M, Old lover = EX, Work = OP, Girl = G, English = E, Politician = MP, Date = D, Best = A1, Girl =G, Boy = B, Department = ENT, Husband = H, Papers = ID, Quiet = SH, Daughter = D, Died = D, Popular = IN, Lady = L, Adult = A