Do Marylanders have a Southern accent?
No.
In the real South, Marylanders are considered “border” people. Their allegiance is for them to determine.
My people were Kentucky, also border people. The same rule applies, though most all Kentuckians consider themselves Southern. Their state was officially neutral during the Unpleasantness.
There are distinct accents throughout the state but I don’t know of any which would be considered similar to ‘southern US.’
I used to have sort of a country accent when I was growing up, but not anymore.
I don't know.
But my son, raised in northeastern Maryland, after enlisting in the Marines and being stationed in Georgia,was often called a Yankee in those areas due to his accent.
When he got out and moved to NYS, the locals often called him out as a Southerner because of the very same accent.
We have a Tidewater ("Tahdwudder") accent.
The ones from southern Maryland do.