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Yes, as long the keyboard in question supports remapping in some way. Ideally through the opensource QMK firmware (and thus Via/Remap remapping GUIs), which lets you change any of the keys to anything + has other features. 
Some proprietary remapping software won't let you change where certain keys are/what the Fn layer does etc, and it's hard to tell how good/bad they are in that respect before buying, since they tend to not be super clear about the exact limitations.
I'm trying to wrap my head around the 75% layout - if I want to have Home+End+Delete on the nav column, is it simply a matter of remapping those keys and having keycaps that fit their respective rows?