Try turning off relative annotation scale so that the text gets smaller as you zoom out:
To do that, right-click on the Annotations folder in the Feature Manager and select Details:
In the Annotation Properties dialog, uncheck "always display text at the same size"
Depending on how high-quality you want to make the image, you might do better creating inserting the part with the sketch into a blank drawing, showing the sketch, import the model dimensions and arrange them nicely and then exporting the drawing to a vector format like DXF or AI, or saving it to PDF. this gives you better control over lineweights, font sizes and your image proportionss.
Thanks for your answer.
This trick with annotation text size works only if I want do screen shot - but then the whole image is quite small (limited by screen size).
When doing "save as" annotations are not preserved.
I've tried to export as DXF but the preview dialog also do not show annotations. Only lines of sketch.
This is screenshot of zommed in version - such quality I would like to achieve for whole sketch:
This is screen shot with fixed size of annotations - overlapping is seen and the whole sketch is low detail (due to zoom-out)
This is screen shot with scaled size (20:1) of annotations - overlapping is gone but text is hardly readable and the whole sketch is low detail (due to zoom-out)
Message was edited: added images