What differences should i expect when making wine with fresh mushed fruits and water instead of juice?
I have only tried making wine with juice before.
Will i need to filter it when racking?
You might need to condition it for longer and use finings to clarify it. Adding pectolase could also help as well.
I think it depends on the fruit you're using as well. There's a lot of documentation online if you search. CitySteading Brews on YouTube have made plenty of videos on homebrew using fruit so that's a starting place for you.
Best of luck with it mate.
Mashed fruit floats, so it can form a "cap" on the top of the container - this can trap CO2 in your fermentation vessel, which can make the yeast unhappy and produce off flavors.
You can punch down the cap periodically to let the CO2 out, or I like to use a (sanitized) mesh bag to keep the mashed fruit together, which generally leaves the edges of the vessel clear for CO2 to escape.
Filtering mixes in a bunch of oxygen, which is terrible for your wine. Just give the sediment time to settle before bottling.