Theory #1: Chris has very rigid ideas about gender roles, so since he's now female, he doesn't want to work.
Chris does have rigid ideas about a lot of things, especially gender. On the other hand, he did not grow up in a household with a stay at home mom. (Which I think is significant given that he clearly thinks his family is the epitome of normalcy.) Plus he wants his sweetheart to have a job. Even when he was still in his more masculine phase (eg talking to Kacey's father about how he would work in a warehouse to support her), he didn't talk about wanting Crystal's mother to stay at home with the baby. Work is actually one of the few areas where he's not sexist: he gets just as angry as female authority figures as he does at male ones, he drew Rosechu as a soldier, and I've never seen him question whether it's possible/appropriate for a woman to do any job.
Theory #2: Chris is just lazy. He doesn't understand how much work being a stay at home mom is and thinks it would be easier than getting a job.
Since he has his tugboat and doesn't really understand how money works anyway, there's no reason why not getting a job needs to entail being a housewife. He could always just stay unemployed and keep playing vidya. Chris isn't a girl with no skills who decides to get married and have kids because she has no way to support herself. This is something he actively wants.
My theory: Chris is profoundly lonely and thinks being a housewife would solve his problems.
If Chris had his ideal world -- a loving wife and baby Crystal -- he would never be lonely. Staying at home on his tugboat with no family except his insane mother, he is incredibly isolated. But if he got a job and moved out of the house, he would have to deal with a world that he perceives as cold, uncaring, and actively prejudiced against autistics. (And lesbian transgenders.) He has never gotten emotional fulfillment by going out and meeting new people. His new church eventually rejected him, the Wallflower rejected him, manajerks kick him out of stores, etc. Being a housewife would allow him to be protected while still having people who were emotionally invested in him around at all times. (He probably also thinks Crystal will be the sweetest girl ever, will never throw tantrums or be bratty, and will always adore her father/mother/tomparent.)