Most are made up and silly.
The only one I've liked was in college I did a "communication style" one. Where it showed a bunch of different like emails, posts, and conversations and asked which you preferred to receive and which you were likely to write.
10 years later I still think about it, cause the goal of the work was to talk about how if you're a certain communication style what to keep in mind with communicating with others. Like tips to not get frustrated with yellows who don't care about facts when sending emails and how to write emails that don't bore and frustrate people if you're blue. (I'm blue green. I can sometimes write long emails)
I thought about it the other day cause a guy was complaining about all these emails that didn't seem to say anything, they were just about feeling good, and he just wanted them to spit it out. Which corresponded to firey red getting mad at green.
So with that context, do you have any that actually had an impact on you?
Probably an attachment style test. Attachment theory is empirically valid, and knowing your attachment style can help you understand relationship patterns: communication, behaviors, emotional needs, etc.
After that, the love languages are a good start to a conversation. Essentially they can help you figure out how you prefer to be cared for, and how you tend to show that you care. The categories themselves are arbitrary, and they're based on observations by a baptist minister who offered relationship counseling. He's not a licensed mental health professional, and the love languages aren't empirically based. One issue I have with his book is that he claims that men tend to have "physical touch" as their love language, and that women should have more sex with their husbands to help them feel loved.
The Big Five personality traits are the most valid of the popular personality tests, but I didn't feel like they helped me understand myself more.