I am a beginner in music, and I like both piano and electric bass guitar. I can spend 2,3 hours per week on music (Online Learning and playing). I am not a musician, but I am playing for joy. I’ve started practice in the bass, and I like the tab notation. Is there anything similar for piano (except the standard music notes notation)? Is it preferable to stick and learn the bass currently and later start playing the piano using the standard note notation?
In the modern world, the most popular alternative piano notation is probably the vertical scrolling layouts that you see in videos like this one:
You can't guarantee that you'll find a tutorial video like that for every piece you want to play, but then you could say the same for sheet music!
Standard notation can be awkward to learn, but it's possibly less awkward to learn it for a keyboard instrument like the piano where the layout of the instrument (with black keys and white keys) actually reflects more of the concepts that standard notation is based on (in particular, sharps and flats).
There's nothing that seriously challenges standard notation for piano. For bass guitar you need to understand both tab and notation. For piano you need notation. There's little point in searching for something 'easier'. Notation already IS the 'easiest' part of piano playing, a minor skill that unlocks all the other, greater ones. Treat it that way, rather than as an obstacle!
There is klavarskribo( https://en.m.wikipedia.org/wiki/Klavarskribo), invented in 1931 to simplify music notation for keyboard instruments, to enable more people to enjoy music. It has obviously not become the new standard, but it has lasted a long time (compared to other alternative notations), and many classical songs have been transcribed in it.
It looks like tablature for key instruments:
I would not advise you to use it, but it's an interesting concept.
Most piano players start with r.h., and learn through the standard dots. That's good, but when l.h. comes out to play, there's often a hurdle in the way - the bass clef is similar, but not the same as the treble.
You could do yourself a favour, and learn bass guitar first, using bass clef. Then on to piano, where that will be familiar.
Also the bonus of being a bass guitar reader will pay dividends later in life - most of us aren't brilliant readers, and lose playing opportunities because of that.
EZ Play Today song books offer a stepping stone into reading notation. They are available in a wide variety of musical genres. They feature melodies in single notes with the note name within the note accompanied by the lyrics and the appropriate harmonizing chord. You gradually begin reading simple standard notation without reference to the printed name.