[Chartjs]-How do I change axis, title, legend formatting on chartjs template

1) you can set font options for title, legend and axes through “font” property of corresponding options’ element

legend: {
   font: {
      color: 'black',
      family: 'Zapf-Chancery, cursive',
      opacity: 1,
      weight: 700
    }
}

You can find more sample in ChartJS documentation.

2) You can use HTML tag br to wrap your title to second line

title: "This is my<br/>long title"