You might want to take a look at the FOCKing thread (github) (its DIY from the ground up inspired by CheapFOCer and based on the MP2-ESC). The design is effectively modular. Power stage, MCU, and V-Supply are all on their own modules. So while I doubt “hot swap” is likely, having modularity and spare modules that are easier to swap is likely doable with such a design.
Edit: Though, in my experience(lol) the power stage tends to be the more expensive part of the board on DRV-based designs. This might not be so much the case anymore but when I did my own batch of CFOC1 & 2s the bulk of the cost came from the FETs. Now we’re pushing more volts instead of stupid amps part selection might be more economical but I’ve not compared. Food for thought.
Regarding the Ubox dual Alu Lite if you scroll down they say “Replacable single board” as one of the changes between the Ubox V2 and the Dual Alu Lite.
I dont think they mention it in any of the other listings though I haven’t really looked all that closely at anything outside of the Alu Lite and Dual Alu Lite. Its also possible im misinterpreting the statement. But hey, the worst they can do is say no.