「早めに着いちゃったからカフェにいるね！」というのは、
I got here early, so I'll be in a cafe!と言えます：
I got here earlyは「早めに着いた」という意味です。
ほかにI arrived earlyも使えます。
「だからカフェにいる」はso I'll be in a cafeといいます。
beの代わりにwait（待つ）も使えます。
「カフェにいるね」という表現ですが、待ち合わせの場所がカフェではなく、早めに着いたのでどこかのカフェに入って時間をつぶす、というようなときは「I will be at a cafe」（不特定なので「a」を使用）と言います。待ち合わせの場所がカフェで、待ち合わせの場所にいる、と言うときは「I will be at the cafe」となります。状況に応じて使い分けてみてください。ご参考にしていただければ幸いです。
All three of these sentences tell the person you are meeting that you arrived early and you will be waiting. Adding no rush is a polite way of saying that you are early, but there is no need for them to hurry because of it. It's a little social grace.
3例とも、待ち合わせの相手に早く着いたので待っていると伝える言い方です。
"no rush"は、早く着いたけど急がなくてもいいよと伝える丁寧な言い方です。これは社交上の礼儀ですね。
I got here a little early so I'll be waiting for you in a cafe.
"In a cafe" is the way to say that in one cafe is where you will be. You may need to tell your friend the name of the cafe so that they can find you. I hope that this helps :)
"In a cafe"とは「（相手の知らない）カフェに」という意味です。カフェの名前を相手に伝えておいた方がいいかもしれませんね。
お役に立てれば幸いです :)
I arrived a little bit early. I'm just waiting in a nearby cafe.
I'm here early, so I'm waiting in a cafe. :)
I'm early and am already here. See you soon. No hurry!
Saying that you arrived a little bit early and that you are waiting in a nearby cafe lets your friend know that you are already there.
"I'm here early, so I'm waiting in a cafe. :) " I sent this exact text to my friend the other day! This lets your friend know that you're ready to meet them and are just waiting nearby. The smiley face makes it more casual and happy.
"I'm early and am already here. See you soon. No hurry!" - I would say this if I was planning on meeting my friend at the cafe itself. By saying this, you are letting your friend know that although you are already there waiting, there is no need for them to rush to meet you because you are the one who is early.
"I arrived a little bit early. I'm just waiting in a nearby cafe."（ちょっと早めに着いたので、近くのカフェで待っています）
これで友達に自分がもう既にそこにいることが伝わります。
"I'm here early, so I'm waiting in a cafe. :) "（早く着いたので、カフェで待っています）
この間これと全く同じメールを友達に送りました！これで友達に自分が既にそこに到着していて近くで待っていることが伝わります。このスマイリーでカジュアルで楽しい感じになります。
"I'm early and am already here. See you soon. No hurry!"（早めに着きました。待ってるよ。急がなくていいから）
私だったらこれは待ち合わせ場所がそのカフェだったときに使います。ここでは、自分は今そこで待っているけど早く着いただけだから急がなくていい、と伝えています。
This is a message you could send to a friend that you have plans to meet with. If you arrive early, or before the time that you planned to meet, you can let the other person know that you are there already.
When the other person arrives, he/she will know exactly where to find you if you say the name of the cafe where you are waiting.
I got to the cafe a bit early, so I'll be here when you arrive.
Sometimes saying that you're waiting for someone can imply a slight inconvenience, so you could say this without implying that you'll be waiting for the person. Maybe you brought a fascinating book with you, and so whenever your friend arrives is fine, but you're still letting them know you're there.
I arrived early and am waiting in the cafe at the end of the street
I got here ahead of time so am having a latte in Starbucks now
When meeting up with a friend, you arrived early and want to tell your friend that you arrived early so will be waiting in a cafe. In this case, you could use any of the above suggested statements. The exact location of the cafe is important also!
Both of these phrases have the exact same meaning and can be used interchangeably to come out to have the same meaning. The main difference between them is the verb usages between the verbs, "to be," "to arrive," and, "to wait." Take a look at these switches as it shows the flexibility that can come within this sentence.
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