Simple but Hard to draw

cybernalin,

To get the dashes to cross (symmetrically) at the intersections, and to bend (symmetrically) round the corners of the (outer) frame, you can set the Dashes individually for each line length as follows:

1) In the Stroke palette, with Dashed Line ticked, click the rightmost option (B. Aligned dashes to corners and path ends, adjusting lengths to fit to Corners and Path Ends, Adjusting Length to Fit), see link below;

2) Choose the desired number of gaps between meetings/crossings of lines (maybe 3 or 4 judging by your latest screenshot); this will be the number of gaps for the sides of each square;

3) For the frame consisting of the four outer sides, simply set the Dash equal to the total path length divided by 96 times the desired number of gaps from 2) (that is twice the desired number multiplied by the number squares passed (48), the latter being four times the number of squares in each direction (12); with 4 gaps that will be 384;

4) Select the (2) centre lines (horizontal and vertical), simply set the Dash equal to the total path length divided by 24 times the desired number of gaps from 2) (that is twice the desired number multiplied by the number squares passed (12); with 4 gaps that will be 96;

5) Going out from the centre lines, select each of the (4) inner lines of the same length (2 horizontal and 2 vertical), repeat 4).

https://helpx.adobe.com/illustrator/using/stroke-object.html#create_dotted_or_dashed_lines

I'm still not quite sure about your request.

Usually, it is not necessary to not expand the appearance in order to be able to have dashed lines.

I'm afraid some more clarifications are required, so one can understand your wish a bit better.

Which version of Illustrator are you using?

Also, what exactly do you mean by "all line must be in dashed and final shape should be in stroke"?

There may be a couple of ways to do what you want, but perhaps you first want to clarify a bit.