All I found was the photo captions below, with not much more detail.
"1921. The captains of Stoke United Ladies and Blaydon Ladies greet each other before the match. Women's football was born in 1894, when a predestined activist by her last name, Nettie Honeyball, founded the first women's team: British Ladies Football Club. (221)"
"1921. Stoke United Ladies and Blaydon Ladies captains kissed each other before the match. Female football's origin was in 1894. Nettie Honeyball, aa feminist activist, founded British Ladies Football Club, the first female football team."
https://cafeblissett.tumblr.com/post/22719937362/1921-las-capitanas-del-stoke-united-ladies-y-delAnother page from a different site captioned it....
"Kiss Before Kick Off
February 1921: Two members of the Lyons girls' football teams kissing each other during a match. (Photo by Topical Press Agency/Getty Images)"
And perhaps the answer that gives reasoning to the kiss, a website from France with an article regarding athletes coming out has a caption alongside the image reading;
"Two female soccer players kiss before the kick off of a match, which was the custom in the 1910s-1920s. (© GETTY IMAGES)"
source:https://www-francetvinfo-fr.translate.goog/sports/foot/sportifs-est-ce-le-bon-moment-pour-faire-son-coming-out_314493.html?_x_tr_sl=fr&_x_tr_tl=en&_x_tr_hl=en&_x_tr_pto=sc