But how long did you play a 4 string bass before you got to that point? Now you have to kind of start over. But it won't take as long.
When I got my first 5 string I also switched from playing with a pick to mostly playing with my fingers. Even after 19 years of playing I felt like a beginner. I made mistakes and plucked the wrong string and had to look at my fretting hand. I forgot the B wasn't the E.
Before that I was playing a fretless P style bass and Ricks.
So it just took effort and time spent on the bass before it was second nature.
I have several fairly identical 5 string basses I made (one is fretless) and my '87 Ibanez as well as my 2 old Ricks, an 8 string. I like to get to know instruments very well instead of jumping around between basses.

especially when going to more than 4 strings. Get used to one bass. When you feel confident switch to other basses.