If you follow my suggestion above, and create a footprint once, you'll use "solid region". This is simple because placing vias doesn't require that you assign them to a net.
^^^ This sentence only applies to creating a
footprint as defined in post #69.
If you insist on being a masochist and want to "add it on" to a circuit board (which requires duplicating effort many times) , you'll need to use "copper area" to define the regions. This requires defining which net the region is connected to, which will be the drain of the MOSFET and
different every time. You'll have to define the net for the stitching vias too.
Hint - place the first via, edit the net property, and copy&paste it repeatedly.
Hint - set the grid spacing to the spacing you want for the vias. Maybe 1 or 2mm.
Use the via tool to create vias.
Suggestion - there's no need to press the limits of the fab house. There's no need to go smaller than a 0.4mm drill with a 0.8 annular ring,
Hint - set the properties on the FIRST one before copy&pasting, Then you only have to do it once.
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