Country flags: flag-icons 7.6.0, MIT licence. See LICENSE.txt.
Source: https://github.com/lipis/flag-icons

west-indies.svg: pre-1999 West Indies Cricket Board flag.
Original emblem: West Indies Cricket Board. SVG representation by Wikimedia Commons contributors, latest revision Tcfc2349 (2018).
Source: https://commons.wikimedia.org/wiki/File:WestIndiesCricketFlagPre1999.svg
Asset: https://upload.wikimedia.org/wikipedia/commons/1/18/WestIndiesCricketFlagPre1999.svg
Rights: Commons identifies this historic design as public domain (Public Domain Mark 1.0).
https://creativecommons.org/publicdomain/mark/1.0/
Changes: none. Rendered in the site's fixed flag frame.
This is the historic cricket flag, not the West Indies Federation's national flag.

Australian state flag SVGs:

au-nsw.svg
Author: Denelson83 (original)
Source: https://commons.wikimedia.org/wiki/File:Flag_of_New_South_Wales.svg
Licence: CC BY-SA 4.0
https://creativecommons.org/licenses/by-sa/4.0/
Changes: None; displayed in a fixed flag frame.

au-qld.svg
Author: Government of Queensland
Source: https://commons.wikimedia.org/wiki/File:Flag_of_Queensland.svg
Licence: Public domain / CC0 as specified on source page
https://creativecommons.org/publicdomain/zero/1.0/
Changes: None; displayed in a fixed flag frame.

au-sa.svg
Author: Robert Craig (Likely Original Designer)
Source: https://commons.wikimedia.org/wiki/File:Flag_of_South_Australia.svg
Licence: Public domain / CC0 as specified on source page
https://creativecommons.org/publicdomain/zero/1.0/
Changes: None; displayed in a fixed flag frame.

au-tas.svg
Author: Unknown author (Proclaimed by Sir Frederick Weld)
Source: https://commons.wikimedia.org/wiki/File:Flag_of_Tasmania.svg
Licence: Public domain / CC0 as specified on source page
https://creativecommons.org/publicdomain/zero/1.0/
Changes: None; displayed in a fixed flag frame.

au-vic.svg
Author: Denelson83 (original)
Source: https://commons.wikimedia.org/wiki/File:Flag_of_Victoria_(Australia).svg
Licence: CC BY-SA 4.0
https://creativecommons.org/licenses/by-sa/4.0/
Changes: None; displayed in a fixed flag frame.

au-wa.svg
Author: Original: Frederick Weld Vector:  Denelson83
Source: https://commons.wikimedia.org/wiki/File:Flag_of_Western_Australia.svg
Licence: Public domain / CC0 as specified on source page
https://creativecommons.org/publicdomain/zero/1.0/
Changes: None; displayed in a fixed flag frame.

County flags (geographic flags, not club logos):

county-derbyshire.svg
Author: Dyfsunctional at English Wikipedia
Source: https://commons.wikimedia.org/wiki/File:Derbyshire_flag.svg
Licence: Public domain
https://creativecommons.org/publicdomain/mark/1.0/
Changes: non-rendering metadata removed; artwork retained.

county-durham.svg
Author: Lewis R
Source: https://commons.wikimedia.org/wiki/File:Flag_of_Durham.svg
Licence: Public domain
https://creativecommons.org/publicdomain/mark/1.0/
Changes: non-rendering metadata removed; artwork retained.

county-essex.svg
Author: Greentubing
Source: https://commons.wikimedia.org/wiki/File:Flag_of_Essex.svg
Licence: Public domain
https://creativecommons.org/publicdomain/mark/1.0/
Changes: non-rendering metadata removed; artwork retained.

county-hampshire.svg
Author: Greentubing
Source: https://commons.wikimedia.org/wiki/File:Flag_of_Hampshire.svg
Licence: CC BY-SA 3.0
http://creativecommons.org/licenses/by-sa/3.0/
Changes: non-rendering metadata removed; artwork retained.

county-kent.svg
Author: Richard Thompson
Source: https://commons.wikimedia.org/wiki/File:Flag_of_Kent.svg
Licence: CC BY-SA 3.0
http://creativecommons.org/licenses/by-sa/3.0/
Changes: non-rendering metadata removed; artwork retained.

county-lancashire.svg
Author: Wereon
Source: https://commons.wikimedia.org/wiki/File:Flag_of_Lancashire.svg
Licence: CC BY-SA 3.0
http://creativecommons.org/licenses/by-sa/3.0/
Changes: non-rendering metadata removed; artwork retained.

county-leicestershire.svg
Author: Hogweard
Source: https://commons.wikimedia.org/wiki/File:Flag_of_Leicestershire.svg
Licence: Public domain
https://creativecommons.org/publicdomain/mark/1.0/
Changes: non-rendering metadata removed; artwork retained.

county-middlesex.svg
Author: The College of Arms
Source: https://commons.wikimedia.org/wiki/File:Flag_of_Middlesex.svg
Licence: Public domain
https://creativecommons.org/publicdomain/mark/1.0/
Changes: non-rendering metadata removed; artwork retained.

county-northamptonshire.svg
Author: Brady Ells & Ian Chadwick and The Flag Institute
Source: https://commons.wikimedia.org/wiki/File:Flag_of_Northamptonshire.svg
Licence: Public domain
https://creativecommons.org/publicdomain/mark/1.0/
Changes: non-rendering metadata removed; artwork retained.

county-gloucestershire.svg
Author: Mjpovey
Source: https://commons.wikimedia.org/wiki/File:Severn_Cross.svg
Licence: Public domain
https://creativecommons.org/publicdomain/mark/1.0/
Changes: non-rendering metadata removed; artwork retained.

county-nottinghamshire.svg
Author: The Flag Institute
Source: https://commons.wikimedia.org/wiki/File:County_Flag_of_Nottinghamshire.svg
Licence: Public domain
https://creativecommons.org/publicdomain/mark/1.0/
Changes: non-rendering metadata removed; artwork retained.

county-surrey.svg
Author: Hogweard
Source: https://commons.wikimedia.org/wiki/File:Flag_of_Surrey.svg
Licence: CC BY-SA 3.0
https://creativecommons.org/licenses/by-sa/3.0
Changes: non-rendering metadata removed; artwork retained.

county-sussex.svg
Author: Unknown authorUnknown author
Source: https://commons.wikimedia.org/wiki/File:Flag_of_Sussex.svg
Licence: Public domain
https://creativecommons.org/publicdomain/mark/1.0/
Changes: non-rendering metadata removed; artwork retained.

county-warwickshire.svg
Author: Vexilo
Hogweard
Source: https://commons.wikimedia.org/wiki/File:Flag_of_Warwickshire.svg
Licence: CC BY-SA 4.0
https://creativecommons.org/licenses/by-sa/4.0
Changes: non-rendering metadata removed; artwork retained.

county-worcestershire.svg
Author: User:Hogweard and The Flag Institute
Source: https://commons.wikimedia.org/wiki/File:Flag_of_Worcestershire.svg
Licence: Public domain
https://creativecommons.org/publicdomain/mark/1.0/
Changes: non-rendering metadata removed; artwork retained.

county-somerset.svg
Author: Leonardo Piccioni de Almeida
Source: https://commons.wikimedia.org/wiki/File:Flag_of_Somerset.svg
Licence: CC BY-SA 3.0
https://creativecommons.org/licenses/by-sa/3.0
Changes: non-rendering metadata removed; artwork retained.