Anubias and Java Fern can grow in low light. Water Wisteria needs high light. If you go with medium light levels, then you should be able to grow them all together.
One thing you have to know about the anubias and java fern is that they have a rhizome which you can't plant under the substrate. You can plant the roots, but the rhizome must stay above the substrate.
Bettas don't really like other fish. Also, a 10 gallon tank would not be enough space for a big enough school of the neon tetras.
Guppies should not be kept with bettas because bettas often mistake the guppies for other bettas and attack them. Guppies also need hard water and bettas need soft water.
Once your tank is cycled, it's not really necessary to test the water every day. It would be good to test it every once in a while though.
When you look for a betta, get one that is actively swimming about. Hold his cup up to another betta and see if he flares.
Make sure there are no tears in his fins, and that he doesn't have finrot. A betta with finrot will have tattered looking fins.
I know you said you wanted a betta with really long fins, but those are not very healthy. Halfmoon, Rose tail, Feather tail, Over halfmoon, and Super delta tail are all tail types that should be avoided. Because of the long fins, those bettas often nip their own fins, they are more prone to finrot, and the have trouble swimming when they get older.
You should also avoid dragon scale bettas. They can get issues where their scales grow over their eyes and gills. They are also very prone to getting tumors.
A canister filter is overkill for a 10 gallon tank.
A 20 gallon does not need a stand as long as you have something strong and sturdy to put the tank on.