I'm running Linear Mixed Models on a dataset. The assumption for homoscedasticity is not being met, however when I remove one independent variable, then it's being met. So all the other variables except this one are homoscedastic. To fix this and make the dataset fit the model better, could I just transform the independent variable which is the issue by cube rooting it? And leaving others as they are? Or do I have to transform all of them if I'm transforming one variable?
Also, is transforming them going to increase any kind of error rates and make inferences difficult? I would really appreciate help with this and I apologize if this is a silly question, as I'm a beginner.