"Aggressive hegemonic" would be an overstatement... it's not like they're emulating the US and sending troops into faraway countries. Still, a more assertive posture than before and one to which regional states will respond in their own ways, which will sometimes overlap. More a continuing round of pushing and shoving around the edges than desperate resistance to a hegemonic power.
China has a long way to go before they can emulate the US.

Indeed there will be pushing and shoving, but the nations are getting ready not to be pushed too far.

The manner in which Vietnam, an old enemy of the US, readily took the US help and conducted naval exercises with the US in the South China Sea, as also the manner in which Philippines took the US help and allowing the US troops to 'rotate' US troops being stationed in the Subic Bay base (from where they forced the US to quit) is indicative of the 'concerns' these nations have towards the Chinese moves.

What makes the Nations wary is that China has scant regards for what the world order feels. They do exactly what they want and that to many is scary!