Can I assume that groundings in electrical circuits can be split?

Schematic-wise both drawings are equal and analysing them makes no difference. It just assumes wires are ideal.

In real life, you can implement how the currents return to battery in many ways, as real life wires have resistance and thus currents flowing in wires create voltage difference, but that can be ignored if your circuit is not a precision circuit.

As others say, your two schematics are electrically identical. If your circuit used more opamps, you could also show multiple VE and VC symbols for the power distribution.

It is common practice to place multiple Ground or Power symbols on a schematic to reduce the clutter produced by explicitly drawing all Ground or Power connections. In more complex circuits, it is common to use "net names" to imply connections for common signals rather than drawing the wire to show the connection.

The schematics is the same in both two versions. If you feel more favorable with second example, then use that way. But it makes no difference at all, the most important thing comes how do you physically connect these points while routing in real application.