The Christmas truce refers to series of widespread but unofficial ceasefires along the Western Front of World War I around Christmas 1914 (Wikipedia). This is a well-documented event.
The photo below is being shared with the following caption:
British & German soldiers of WW1 declare an informal truce and play a match of football between trenches, Christmas 1914
That is not true. It is a black and white version of the re-enactment photograph by Virginia Mayo (Associated Press).
The next photo is often shared with a caption “German and British troops forgot about the war for a moment and played football in the Christmas Truce of 1914 in WWI”
That is also false: the photo shows only British soldiers playing football in Salonika, Greece 1915.
I’m not aware of any photos about the alleged football matches during the Christmas truce of 1914. In fact, many historians agree that there wasn’t a single organized football match between German and British sides.