hmmm i think for french what i would suggest is having them all in one tag even if it makes one text look a bit long, like
"{0}blabla il{/0}{1}blabla elle{/1}{2}blabla iel{/2}"
in this case only the relevant text would show up!
however since french is very gendered it might be tedious to type so often so using the pronouns as variables option might be a bit easier for you. the example i have in the tool is for english but you could do something like
default iel = [
__("il"), #0
__("elle"), #1
__("iel"), #2
]
default e = [
__(""), #0
__("e"), #1
__(".e"), #2
]
and in game type something like "[iel] est mon ami[e]" and it would show up as either "il est mon ami", "elle est mon amie" or "iel est mon ami.e" depending on the current pronoun (and adding other variables as necessary)
*if you want to translate you would need to use [iel!t!c] &c. but if you have no plans just typing it like [iel] would be sufficient