knowledge - Cryptic with missing capitals

Solve the clues and fill the grid. Each clue is missing a different European capital city.

Across

1. Funny beret men strike $??$ to convene (4)
3. Containers found in a $??$ plaza (4)
5. Ten $??$ site's leaders return after first state, shortly (4)
6. Ethnic group is $??$, locally (4)
7. Dmitry's $??$ chamber first for union's capital (4)
8. Hideout between left and right, return $??$'s finals (4)
9. Certain banks of $??$ river encircle central dome (4)
10. $??$'s extremities leave metals for baseballers (4)
11. Stalk Dorothy's aunt following the heart of $??$ (4)

13. Moody people's fringe expressions outside $??$'s borders (4)
14. Half-heartedly, $??$ first lady makes money (4)
15. In the middle of chaotic $??$, doctor gets cut (4)
16. Asteroid buried in the back country of $??$ (4)
17. Constituents of $??$'s republic passed with flying colours (4)
18. Arrest $??$'s top three; capital punishment follows (4)
19. Listen, Sparta $??$ to be overflowing (4)

Down
1. Created the second-to-last little $??$ statue with no rim (4)
2. Wanting an I, $??$ head master leads to transport (4)

3. Friends immediately south of $??$, third one climbing up (4)
4. $??$ couple hides in tube below street under pressure (8)
5. Head of state visits Namib and Gobi for $??$ Fingers, among others (8)
11. $??$'s central assistants preparing leaders for strike (4)
12. $??$'s central trio on top-tier market, briefly (4)
13. Henry IV leaves the last bits of $??$ cheese (4)

Note:

For the purposes of this puzzle I did not include Baku, Nicosia, Tbilisi or Yerevan (all of which could be European depending on which definition one uses).

Answer

1. Funny beret men strike ?? to convene (4)

Insert BERN; solution is MEET: (BERETMEN-BERN)*

3. Containers found in a ?? plaza (4)

Insert BERLIN; solution is POTS, found in POTSdamer Platz

5. Ten ?? site's leaders return after first state, shortly (4)

Insert ATHENS; solution is DECA: AC(ropolis) backwards after DE(laware). I'm not terribly confident about this one.

6. Ethnic group is ??, locally (4)

Insert ROMA; solution is ROMA (Italian name for Rome)

7. Dmitry's ?? chamber first for union's capital (4)

Insert MOSCOW; solution is DIMA: DUMA with I in place of U

8. Hideout between left and right, return ??'s finals (4)

Insert SOFIA; solution is LAIR: IA between L and R

9. Certain banks of ?? river encircle central dome (4)

Insert PARIS; solution is SOME: banks of S(ein)E encircle (d)OM(e)

10. ??'s extremities leave metals for baseballers (4)

Insert LJUBLJANA; solution is METS (METALS minus AL)

11. Stalk Dorothy's aunt following the heart of ?? (4)

Insert PRISTINA; solution is STEM: EM after ST

13. Moody people's fringe expressions outside ??'s borders (4)

Insert MONACO; solution is EMOS (ES outside MO)

14. Half-heartedly, ?? first lady makes money (4)

Insert RIGA; solution is RIAL (RI(g)A + L)

15. In the middle of chaotic ??, doctor gets cut (4)

Insert MADRID; solution is AMID: (MADRID-DR)*

16. Asteroid buried in the back country of ?? (4)

Insert BUCHAREST; solution is AMOR, found backwards in ROMANIA

17. Constituents of ??'s republic passed with flying colours (4)

Insert SKOPJE; solution is ACED, found inside (North) MACEDONIA

18. Arrest ??'s top three; capital punishment follows (4)

Insert STOCKHOLM; solution is STOP: STO(ckholm) + P(unishment)

19. Listen, Sparta ?? to be overflowing (4)

Insert PRAGUE; solution is TEEM (apparently "Sparta Prague" is a sporting team; thanks to Fillet for finding this)

Down

1. Created the second-to-last little ?? statue with no rim (4)

Insert COPENHAGEN; solution is MADE: (Little) MERMAID with its second letter moved to the end (MRMAIDE) and letters of RIM removed

2. Wanting an I, ?? head master leads to transport (4)

Insert TIRANA; solution is TRAM: T(i)R(an)A + M(aster)

3. Friends immediately south of ??, third one climbing up (4)

Insert VADUZ; solution is PALS: ALPS with third letter P climing up to top

4. ?? couple hides in tube below street under pressure (8)

Insert BRUSSELS; answer is STRESSED: SS in REED below ST

5. Head of state visits Namib and Gobi for ?? Fingers, among others (8)

Insert VIENNA solution is DESSERTS: S inside DESERTS

11. ??'s central assistants preparing leaders for strike (4)

Insert OSLO solution is SLAP: (o)SL(o) + A(ssistants) P(reparing)

12. ??'s central trio on top-tier market, briefly (4)

Insert SAN MARINO; solution is MART: MAR on top of TIER

13. Henry IV leaves the last bits of ?? cheese (4)

Insert AMSTERDAM; solution is EDAM: ERDAM minus IVth letter of HENRY

Grid:

      M E E T     P O T S

D E C A     R O M A     T
E     D I M A     L A I R
S O M E     M E T S     E
S                       S
E     S T E M     E M O S
R I A L     A M I D     E
T     A M O R     A C E D
S T O P     T E E M

Notice that

the solutions, not merely the spaces, are rotationally symmetrical.

Credit where due:

I didn't figure out 19a myself and probably never would have; Fillet found it; please consider upvoting their answer if you like this one.