Most good football officials would struggle at becoming a basketball official. And most good basketball officials picking up football would find it very easy.
Tony made some very good points about the two sports. But as a basketball officials you cannot hide from coaches like many do on a football field (umpires, back judges, referees). The fans are closer in basketball, which many football officials have admitted bothers them. The environment can be louder and more intense in basketball (I have to emphasize the word
CAN). You have to be in over all better shape as a basketball official. I also feel it is harder to advance in basketball. This might vary by area, but you are dissected more as a basketball official. And the bottom line, you are working more games, more confrontations, more physical stress on your body. And being a basketball official is much more of an individual sport to officiate. You are not relying on a crew or a group of people to cover you. In basketball you are judged largely as an individual and what you do as an individual. In football you can hide on a crew and your crewmates can protect you. Not the case in basketball. And in basketball you have to be able to do all the things your partners can do in that game. In football you are playing a position. As a Referee I have totally different responsibilities in a game than a backjudge. In a basketball game, all a Referee does for the most part is throw the ball up at the beginning of the game, but after that we are all equal.
An assignor in my area that is an accomplished football and basketball told me,
"Football is a game of rules, basketball is a game of judgment."
I will also say this. The friends that you gain in football tend to be deeper than those of us that work basketball. You spend a great deal of time with the same people during the football season. In my state we only have a 9 week season. So I will work at least 9 weeks with the same people and learn a lot about my partners and their lives. I am lucky out of the 40 varsity games in basketball, I am lucky to work with the same official more than once.
Officiating in general is a great experience and picking up a sport will do nothing but help you in another. Just understand that your expectations have to change when you move to another sport. But that does not mean it cannot be a lot of fun.
Peace