Embedded logo in email

Hello everyone,
I’m new to this community =).
I am a junior developer. I ran into a problem that I need some perspective and advice on.
I have just arrived on a sylius project already in place, the general emails of the site go through the Sylius mailer bundle. The problem is that the main logo of the company is not displayed in some people (external url) then Google (gmail) does not take images in base64. I would like to put the logo in content integrated into the email in the simplest way without changing everything that is already in place on the site.


I would like not to change all the configuration already in place.
But I think I’ll have to switch everything to the symfony mailer bundle.

Thank you in advance for those who will give me solutions.