Preview opens multiple (100+) images in jumpy sequence

Whenever i choose to open multiple images in one window, more than 100 at once, the images are not arranged in the sequence of file name. I need to right click on the thumbnail sidebar space to set it to arrange by Name amongst other criteria. When i look further in the jumpy sequence, I think it opens images created in Mojave first, and followed by images created in or copied from older OS.

In older osx, Preview arrange all images by file name by default. How can we set it to arrange all images by file name every time?

Also, why does Preview prompt and ask for confirmation every time we open multiple (a lot like 100+) files? Is there a way to do away with the prompt? It is slight but annoying.