Decide what absinthe is doing in your recipe: anise flavor, herbal bitterness, or both.
Pick the closest match from the table/entries and apply the listed ratio (use the lower ratio for sweeter liqueurs).
For cocktails, stir gently and taste once diluted; for baking, add early and bake to mellow harsh bitterness.
If the substitute is sweeter, add a small pinch of salt or a squeeze of lemon; if it’s too mild, add ¼ of the substitute amount.
Recheck after the first pour/bake: absinthe-style flavor blooms as it mixes or bakes, so minor adjustments go a long way.