I see that the original post on this is now marked "answered", so I suppose we cannot reply. This is in regards to Photoshop Elements not updating to be compatible with the latest Mac update. As none of the time and labor intensive suggestions from Adobe have resolved this issue of the system freezing nonstop when using any type of brush tool, I suggest we flood social media with our complaints and warn people NOT to buy Photoshop Elements until Adobe corrects this. I was told that I had to buy PSE 19 to resolve the issue, which I did, and it only got worse, so just want to warn everyone else to not waste their money.
Sorry for bad experience, let us help make this right. Could you please try updating to the latest patch released today by going to Help > Updates menu. Once updated, please check if you have the build 17.0 (20190220.m.128867) (Adobe Photoshop Elements Editor > About Photoshop Elements menu) and let us know if it helps with the issue.