Every digital camera I have ever used has options for naming the files that are created.
I always set the cameras to Continuous file naming so every shot get the next number and never repeats until you get to the max number that particular camera allows, usually between 10,000 or 99,000 shots then it starts back at #1.
But you can also change the starting character of the file name and or use a number.
For the 2 Leica M8 cameras I have the file name always started with L and then a 1 then 00001 L100001. But you could change that first number. So on one of them I set it to start with a 2, L200001. And I made sure the date and time was set correcly on both cameras. This way in Lr when you sorted by Capture time no matter which camera I used, if and when I used both on the same shoot, all the images would Line up by the date and time of when the shot was taken. And if I sorted by File name, In Lr or by the File manager program, one cameras shots would be listed in order before the other.
Do not ever set the camera to Repeat the File naming after a Format of the card in the cameras.
So as to your problem that the images are not in order by capture time that is either you have the camera set to Reuse the File naming, You Renamed the files on import and LrC usually screws that up becuase it does not import images from # 1 through # whatever. It may pick and choose images at random on import making the File Renaming be all over the place compared to the Capture Time, or you are renaming on Export and that is not going from the First shot, Capture Time, to Last Shot, Capture Time, and randomly picking image to export and numbering 1 -2 -3 or whatever out of sequence from the capture time