Any way to change the position of the /title command?

What you had suggested about using "invisible characters" is the correct approach to this problem, it is likely you were not using the correct ones.

A normal title command looks as follows:

/title @a title {"text":"This is a title!"}

And will show in the center:

However, after adding the "invisible characters":

/title @a title {"text":" \u0020 \u0020 \u0020 \u0020 \u0020This is a title!"}

The title will be skewed to the right:

To skew a title to the left, you would simply add the characters after the text instead of before it:

/title @a title {"text":"This is a title!\u0020 \u0020 \u0020 \u0020 \u0020 "}

Which will yield:

Mess around with different amounts of these characters until you reach the desired result.