"脚步沉重地行走" can be translated into English as "to walk with heavy steps" or "to trudge along".
"To walk with heavy steps" directly describes the action of walking with a sense of weight or difficulty in each step.
"To trudge along" implies walking slowly and with effort, often due to fatigue, heaviness, or a difficult situation, which also conveys the idea of walking with heavy steps.
Both expressions capture the essence of walking in a slow, labored, or weighted manner.