Painting Landscape like a TileMap grid

Hi UE enthusiasts!

We are developing Thawed Waters - A boating adventure of the old priest who stands against the ruthless corporation practising animal testing.(Thawed Waters on Steam)

Due to the change in scope, we are trying to port our game from 2D to 3D, as we need 3D physics in the gameplay. Earlier in the 2D setup we used TileMap for the ground. Now we are using Landscape.

Issue: We need to paint the landscape in square grids like the way a tilemap is constructed. We tried using the square alpha brush, with 0 falloff but still, the texture was blending at the edges. To fix this we changed the blend mode to height, which gives crisp edges but has rounded corners and uneven rectangles with some artefacts.

How do we paint the landscape in a grid-type manner with a square brush which has non-blending edges?

Thanks in advance for any suggestion