You cannot physically pass over any rivers or lakes when traveling from Mbabane (the capital of Eswatini, formerly Swaziland) to Egypt. These two locations are separated by thousands of kilometers of land across southern and eastern Africa.
Travel between them requires air transport or overland routes through multiple countries (e.g., South Africa, Botswana, Zimbabwe, Zambia, Tanzania, Kenya, Ethiopia, Sudan). No continuous waterway connects the two.