Currently, the Equation Editor does not appear to have options to control font or color directly. I found an old topic from 2016 that implied that an adjustable font size was being added, but it looks like this has since been removed as I cannot find it (if it is there, it is not very obvious). The following have been my attempts to increase the font size:
Using the Font Size controls in the RCE changes the surrounding text, but not the equation.
Editing the Width/Height in the HTML Editor changes the size in the preview, but it reverts back to the original size when the page is viewed after saving. The preview shows the size I want if I go back to Editing the page.
Clicking on the Equation and dragging the boxes increases the preview size, but it reverts back to the original size when the page is viewed after saving. The preview shows the size I want if I go back to Editing the page.
I know that I can manually add the tags for font size when creating the equation. However, I do not know LaTex well and really do not use a lot of equations in my content, so I do not have a heavy need to learn it. I relied on a website that lets me edit LaTex online, then copy that over to the Canvas Equation Editor to get the desired result.
That site, LaTex Equation Editor, has some tabs for Font and Color. That made it very easy to get the desired outcome. Adding the color option would be helpful. I could see many students benefiting from teachers putting color coded example equations in their lessons. It would be awesome if Canvas could add similar tabs to its Equation Editor to make it easier for all users to edit those two aspects of an equation within Canvas, without having to learn the codes to edit those features.