I'm still waiting to hear back from people on different matters, but there hasn't been a reply from them yet.
But please reply to this email, as I would like this one to be prioritized.
ご質問ありがとうございます。
① "I'm still waiting to hear back from people on different matters,"＝「まだそれぞれ違う案件で人々からの返事を待っています」
"but there hasn't been a reply from them yet."＝「でも、それらからまだ返事は来ていません。」
② "But please reply to this email,"＝「でも、このメールには返信して下さい」
"as I would like this one to be prioritized."＝「これは優先したいメールなので。」
ご参考に。
I'm still waiting for replies on all of them, but please respond to this one first.
他にも、状況に応じた表現として、
・I'm waiting for responses on the others, but this one needs attention first.
・I haven't heard back yet on any, but could you prioritize this one?
関連語や表現としては、
・prioritize（優先する）
・response（返事）
・urgent（緊急、急ぎ）
アメリカ合衆国 
