As far as I can tell none of those drawings on the Beavis audio site will get you A->B and B->A action with just one press, which sounds to me like what you want.
If you just need a few strip loopers, then those drawings will work, but you will still need to step out of your overdrive before stepping into your fuzz/wah.
A Boss LS-2 will do the A->B thing well, or a modified version of that drawing will work also. I am too lazy to work up the modified drawing now, hopefully someone will chime in

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