Hi.
Yes it should be possible.
But you would need some assets like Photon for multiplayer.
Almost anything what can be done in unity can be done with playmaker.
i would start by making a character and set up movements and attacks.
Then Have a 'Data' fsm to hold the stats for the character, you can use some arrays for data per level (damage, magic/physics defense etc.)
later you might want to connect the data with xml (slow loading) or Scriptable objects (very fast but needs some coding)
For easier access to all your character data, as you will be balancing regularly.
here is some info on scriptables :
https://hutonggames.com/playmakerforum/index.php?topic=20829.0and a tutorial video :
i would recommend to use scriptables but if you want to use xml you should search you tube for "Playmaker xml"
you should find several videos (including some of mine)
when using xml, its best to load you xml into arrays or hashtables when loading scenes as getting data from xml directly is slow.