Is it too late to re-pot inside plants?

I repot plants all year long.

No way! Not all plants will respond well, but most plants can be repotted any month of the year. If you want to divide plants as you repot, be extra careful with the roots, add new topsoil, and use root stimulater. Water daily at first, then start weening the plants, especially succulents, back to watering once a week or less. Best wishes ☺️

No, the environment doesn't change inside so you can repot plants all year long.

Hello. It is never too late unless they have died. I usually repot mine in winter when I get the itch to get my hands in the dirt.

Since they are inside plants, you can re-pot them any time.