Most of what I have seen about art journaling recommends that you use the paint you have access to. This is the best advice that I could give. If you can only afford some cheaper craft paints for mixed media supplies, then that is fine. They are very good for some things. I had the Liquitex Basics Acrylic set of 48 for a long time and I was doing nothing with it. More evidence of my phase of buying art supplies even when I did not have a purpose for them.
The Americana Craft Paints have a wide range of colors which is nice when you are just using them without the need to mix up a color to finish a large project or trying to use them for a wider spread coloring. Of course, they are more prone to being chipped or scraped off once they are dry because they do not have the binder in them that Liquitex does. Since they do not have that binder it is possible to use Prismacolor pencils over them. The end result can make for a very neat effect. Of course, they could be mixed with the acrylic paints, but it is likely to come out as a mess since the Americana paints also have thinner coverage. Because I use black gesso they are often too thin for any appreciable cover. Painting them onto a black background means that I have to paint them several times, which can become difficult if there are several objects I am covering in the paint. Since they are so thin, it’s actually best not to use any water with them so the pigment itself does not become diluted.
Liquitex acrylic paint still achieves some of the same results. It does have a binder in it which gives it something of a rubbery sheen once it dries. It is far less likely to scrape or chip off. Because this paint is first meant to be used on canvas it is much more forgiving of using water with it, although unless you are making a wash, I do not advise that you add a lot of water on paper. Because of this binder, it is much thicker so it might need a little bit of water when it is first taken out of the tube. It has a lot better coverage so even bright colors can show up against the black gesso. Usually painting on a second coat makes even thinner colors (like bright yellow) look bold.
While these paints can be mixed the end results would not be pleasant to look at. I find the best results when I can switch between the craft paint and the acrylic paint on the same art journal page. Craft paint only goes on with the correct brush, so trying to use a flat brush with it can make it look patchy with some spots getting the look of thinner paint and some spots looking like thicker paint got used. Ranger makes a multi-purpose tool that is meant to be used with both ink (for stamping) and paint. Craft paint is meant to be used on crafting projects so using the acrylic paint for a crafting project can get awkward. By the same token using craft paint on canvas can look very thin and the end result is much more susceptible to being scratched or scraped off. When using craft paint on canvas it can also have a gritty feeling after it dries and will only work against canvas if the flat paintbrush is used. Because I have not used craft paint for very long, I am not sure how long it would last but I would not expect it to last long without the same binding agent. But as far as price goes, the craft paint is cheapest and though it would be moot if your local art supply store carries acrylic paints, craft paints are very likely to be what you have easier access to.