This could be an issue with Create itself. But no Create method of moving fluids can pull water from the Cooking for Blockheads Kitchen Sink block, despite it being a water source. I have seen it used as an infinite water supply in other modpacks in the past.

I suspect it may not hold an internal inventory of water, which may be why create cannot pump from it. I'll look into that.

It can be ignored when using a deployer using a bucket on the blockspace where the sink is located