"Julia and Neha are beautiful."
Translation:जूलिया और नेहा सुंदर हैं।
Many adjectives that end with a vowel (आ / ए / ई) can be changed to end in the others to suit the subject of the sentence (like अच्छा / अच्छे / अच्छी) but verbs ending in consonants are treated without gender and are the same for all subjects, सुंदर will always be सुंदर regardless of who you're talking about.
Pretty sure you meant adjectives, like सुंदर in which case yes, there does seem to be a general rule there. If an adjective ends with a consonant there isn't a way to conjugate it, so yes.