I am not on title

We own 3 rental properties that are under my spouse’s name only. It made more sense at the time because my spouse had the income and the high credit score.
Now we want to refinance these properties, but now I am the one with the income - how long do I have to be on the title prior to the loan, or can we just change it totally to my name and then refinance (??).
(We also have the same situation with our primary residence)

You can just add yourself to the title and refinance the properties. However your wife will have to remain on the title as she is the current owner.