Do you like it? This verb placere seems to have a active form but a passive meaning, expressed in English by "Is it pleasing to you?" where "it" is a dummy subject, found in Middle English in sentences like "It thinketh me" (I think), or in modern English in sentences like "It's raining on us again!"
Does anyone know what this type of verb is called in Latin?
It's not passive voice. It's just that the different languages make the subject and object different things. Passive voice would be "It is liked by me." That's still me experiencing the liking. "It is pleasing to me" actively has the thing doing the pleasing. Passive voice there would be "I am pleased by it."