Communication between subnets without routing

Hello,

My 192.168.10.1/24 subnet is coming to a saturation. The hosts are connected to a server (192.168.10.10/24) that manage them all.

Since I need to expand the subnet to add new hosts, but I'd rather not rely on routing, could I extend the subnet mask of the server (192.168.10.10/23) and add the new hosts on 192.168.10.11/24?

I feel that it should be working but it seems to be non-standard to say the least…

Can you please explain whether this approach is relevant or not?

Thanks a lot.