Moto Saikyou Yuusha No Saishuushoku summary:

Dan was “the strongest and bravest” when he was young. But because of his lazy life, he is now a divorced, unemployed old man! He tries to earn money through quests for a living, but age has taken its toll on his strength and all that! He was approached by a silver-haired elf, a handsome man, and an S-rank adventurer… a young man of today’s generation!