Draw, or imagine a diagonal line down the center of the switch, so it is in two sections, like your original one. The only difference is that the new switch, has the com(mon) side swapped/inverted with the L1 & L2 end.
Com is common
BTW there really ought to be a short earth wire link, between the earth terminal of the metal back box, and the earthing terminal of the switch. There doe appear to be an earth wire on the back box terminal.
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