The phrase "in different areas" is correct and usable in written English. It is often used to refer to different fields or topics. For example, "For this project, we need to consider the environmental impact in different areas.".
It is pronounced differently in different areas to ease pronunciation.
Change comes at differing paces in different areas.
Also, it is possibly differently delayed in different areas.
"Is it different in different areas?
"I just have pain in different areas".
Each profession is strong in different areas.
Surface qualities vary in different areas from glossy to matte.
Since I tried Ludwig back in 2017, I have been constantly using it in both editing and translation. Ever since, I suggest it to my translators at ProSciEditing.
Justyna Jupowicz-Kozak
CEO of Professional Science Editing for Scientists @ prosciediting.com