You can change the citation style in your document. Go to the Citation Style tab in the Mendeley Cite panel and choose a style from the list. Click on Update citation style to confirm. All citations will then be reformatted to follow the chosen style.
If the style you want to use is not in the list, you can find additional styles by clicking on Select another style. Search for and install the style of your choice. This style will then be added to your list. (Footnote styles are currently not supported in Mendeley Reference Manager. If you want to use a footnote style you can use Mendeley Desktop.)