The short answer: Your signature can reach Ukraine through three working routes: a representative acting under a power of attorney signs in your place; you sign at a Ukrainian consulate, whose certification Ukrainian recipients accept most readily; or you sign before a Canadian notary and the document travels with an apostille and certified translation. The main caveat: some acts — certain bank procedures, some in-person notarial matters — are legally tied to physical presence in Ukraine, and a lawyer confirms per act whether a substitute exists.
This situation usually means identifying what the signature is actually for. A contract, a corporate consent, or an application can normally be delegated or certified abroad. Acts attached to your person by Ukrainian law — like certain statements before a notary about personal status — carry stricter rules, and the route is chosen per act rather than as a blanket answer.