View mode can't be changed just for one folder. It's a general setting. The behavior should be similar to that of windows explorer, that it can be changed differently for each folder, and others won't be influenced SOFTWARE/OS VERSIONS KDE Plasma Version: 5.21.4 KDE Frameworks Version: 5.81.0 Qt Version: 5.15.2
It can be. Dolphin Settings window > General page > View: Remember display style for each folder