message font

Hello. I would like to make slightly bigger the font that I use to send messages. But this also changes the font size of the messages I receive. Is there a way to change the fonts of the messages I Send but not the fonts of the messages I receive?

I am using Mail > Preferences > Fonts & Colors > Message Font.

The default is Helvetica 14. If I change it to Helvetica 15, that is nice for the messages I send, but sometimes it is too large for the messages I receive. I would like to leave intact the font of the messages I receive. Thanks.

I am using macOS Catalina 10.15.7