Create new variables like mcplural. Set it to true when the pronoun is “they”. You can then use multireplace to check if this variable is true or false and output the correct form.
Yep, that’s the idea. Alternatively, you can create variables for common conjugations. Depending on how often you are using conjugated verbs, you might find variables easier.
For example, you could create friend_s where friend_s = "s" when the friend is binary and friend_s = "" when the friend is non-binary.
Then, any time you use a verb that drops the s in the plural, you just write:
${friendhe} read${friend_s} and write${friend_s} every day.
I personally find this easier than multireplace if you have a ton of gender-variable NPCs.
Both options seem pretty easy, and I only have three gender variable characters, but MC and MC’s friend are always the same gender, and making MC’s non-binary brought up some coding issues I didn’t think would be an issue til I started playing out things myself