how can i swap alt & command keys?

hi, i'm suddenly using a windows style keyboard with my mac. it's a great keyboard, but the start/command and alt/option keys' positions are swapped compared to my muscle memory of mac keyboards. i'd like to swap them. is this possible within BTT?

bonus points if i can also remap altgr-> Rcommand, fn-> Ropt, menu-> Rctrl, Rctrl -> fn, so that it exactly matches the layout i'm used to...

Basic remapping can be done in system preferences => keyboard => modifier keys.
For more advanced remappings you should use the app "Karabiner Elements". It's better for this use case.

look at that, you're right! that got me 75% of the way there! (aside from the fn & menu keys) that's probably good enough tbh, thanks so much

I have a similar situation to the OP but I have a window-style mechanical keyboard connected to my MacBook Pro.

I switch between clamshell and laptop mode, which means I need to switch my key mapping/system preferences often.

I was using Karabiner to remap the alt/cmd keys only when I'm using the mechanical keyboard, but I was looking to move away from kernel extensions.
I was hoping that BetterTouchTool could do this, but from the answer above, I'm guessing I'll have to stick with Karabiner for this situation?