QGIS 3.0 to 3.14 π (https://qgis.org/en/site/forusers/dow...)

1. Plugins needs to be installed (Manage and install Plugins...): Polygon Divider QGIS Plugin (Now available for QGIS 3)
1.1. Polygon Divider: (By Area method or By Number method)
This plugin divides polygons into smaller 'squarish' polygons of a specified size.
Polygon Divider takes a polygon and efficiently divides it into a number of 'squarish' polygons of a defined size, which is useful for a multitude of applications such as land parceling, environmental sampling, and so on.
This plugin can work well on some quite complex polygons even if they are very large.

This plugin divides a given polygon into a number of smaller 'squarish' polygons of about 1000m2 (it would be exactly 1000m2 if the polygon happened to have an area that precisely divides by 1000).

There are two options available to the user when dividing a polygon:
A. The absorb method, whereby all of the polygons are slightly larger than the requested size, in order to 'absorb' any oddsized 'offcuts' that would otherwise be left behind.
B.The other alternative would be the offcut method. In which all of the polygons would be the precise size as requested, except one, which is the 'offcut'.

Each output polygon inherits all of the attributes from its parent, as well as the following additional attributes:

ps_id: a unique integer ID for each output polygon
ps_uuid: a version 4 uuid
ps_area: the area of the polygon
ps_repPointX: the X coordinate of a point guaranteed to be within the resulting polygon (not necessarily the geometric centroid, as this is not guaranteed to be within the resulting polygon)
ps_repPointY: the Y coordinate of a point guaranteed to be within the resulting polygon (not necessarily the geometric centroid, as this is not guaranteed to be within the resulting polygon)

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