Is there any way at all this could be ported to 1.16? i would greatly appreciate this as this was JUST the mod I was looking for, thanks.

I don't have any plans to back-port it to 1.16.5, but the stuff is open source, so someone else could do the port if they want, the primary code for this mod is this section of the ThutCore api:

https://github.com/Thuts-Mods/ThutCore/tree/1.18/src/main/java/thut/api/block/flowing