Flashforge creator pro 2 with PLA, standard quality preset, textured removable magnetic bed on the build plate.
The first lines are straight, but as it makes more parallel lines to build the layer, it starts to develop a scalloped pattern. This creates issues with smoothness when it fills back to join it from the other side later. I’ve leveled the build plate, although I suspect it’s not perfectly flat and maybe slightly higher in the middle. Is this my problem? It appears to have the pattern even away from the middle if that makes sense.
This is a flashforge creator pro 2 (in original comment). I’m not sure how to characterize the distortion, but the standard leveling routine puts the extruder in 3 locations near the screw adjustment. After adjusting spacing with a sheet of paper (included, calibrated thickness), it puts the extruder down on the center. The center is always higher than the 3 calibration points, often significantly.
Well then I have bad news. You will have to get your bed straight, be it by replacing or some sanding on a flat quartz block. Maybe you could even mill it. One last test I would run is trying to print without the bed heater just to see if the warping gets any better.
A hackier solution is mesh leveling, but in your case it will still produce parts that aren’t flat.
Also back the nozzle off from the bed by about 0.05-0.1mm in the meantime to get some semi usable results.