Grouping in Fusion

Is there a way to group clips in fusion tab like in the color tab without using an adjustment layer? I want to make changes to my delta keyer that I'd like to get applied to a larger amount of clips.

No.

bummer.. copy & paste, copy & paste, copy and.....

Still a newbie to Resolve, and not too familiar with the delta keyer - but I'm wondering if you can connect the Inspector Panel settings between keyer nodes the way you can with, say, the transform size and position values by right-clicking the name of a parameter and selecting "Connect To"...?

It's not exactly what you asked, but if you want an adjustment to apply to several nodes at once it would work, if supported.

You can achieve this by instancing nodes.
To do so, copy your desired node, and instead of ctrl+v you use the shortcut ctrl+shift+v to paste an instanced version of your node. Instancing is indicated by additional green lines between both nodes. you can then deinstance selected attributes if you desire for individual modification, all other values are shared and updated between the instances.

This is true, but instancing doesn't work across Fusion clips, as far as I can tell.
So if you have multiple clips inside one big Fusion clip, this will work.
But if you have multiple Fusion clips on your Resolve timeline, they are seen as seperate entities, that cannot be linked together.

Sounds like a job for the development team