Modifying individual tick labels in R Plotly
Solution 1:
At the time being this isn't as straight forward as xaxis=list(tickfont=list(color=c('red', 'yellow', 'blue'))) since the color of the tick labels are associated with the properties of the axis and not the individual ticks. You can assign different colors to different parts of the visible axis, but you'll have to add extra axes. This has been done in detail here: Coloring the axis tick text by multiple colors