How to pull date/time in french format for wordpress post?

You need to alter the format of the date/time based on language. This is done by altering the parameters in the_time function. See below for change options. Put the code into the if statement (as an example):

<?php if(ICL_LANGUAGE_CODE=='en'){ ?>
    Last updated <?php the_modified_time('F j, Y'); ?>
    at
<?php }else{ ?>
    Mis à jour le <?php the_modified_time('j F Y'); ?>
    à
<?php  } ?> 

You could make it even simpler by adding the time in the same function rather than calling each 2x. This will save time and space.

<?php if(ICL_LANGUAGE_CODE=='en'){ ?>
    Last updated <?php the_modified_time('F j, Y /a/t g:i a'); ?>
    at
<?php }else{ ?>
    Mis à jour le <?php the_modified_time('j F Y /à h /h i a'); ?>
<?php  } ?> 

I’ve only shown for modified but you can remove modified_ above and it will work for the creation date.

Notice for the french I changed g to h to move to 24 hour time.

See here for more info:

https://codex.wordpress.org/Formatting_Date_and_Time