asita no mendan wo gogo ni henkousasete itadakitain desu ga, yorosii desyou ka.

の links two nouns.

• 明日 = tomorrow
• 面談 = interview, meeting, consultation
• 明日の面談 = tomorrow’s meeting/interview or the meeting scheduled for tomorrow

In English, we often use ’s or a longer phrase like the meeting for tomorrow. In Japanese, の does that linking job.

を marks the thing being acted on.

Here, the action is 変更する = to change.
So 面談を変更する means to change the meeting.

Even though the sentence becomes much more polite and longer with 変更させていただきたい, the basic object is still 面談, so it still takes を.

に marks the target result of the change.

So:

• 面談を午後に変更する = change the meeting to the afternoon

The meeting is being moved into the time slot of the afternoon, so に is the natural particle.

Using を would not work here, because 午後 is not the direct object.
The direct object is 面談; 午後 is the new time.

It is a very polite expression. Breaking it down:

• 変更する = to change
• 変更させていただく = literally, to humbly receive the favor of being allowed to change
• 変更させていただきたい = I would like to be allowed to change it

In natural English, this usually just means:

• I would like to change it
• I would like to ask to change it
• I would like to reschedule it

The important point is that this form sounds very respectful and acknowledges that the listener’s permission or understanding is needed.

Because 変更したい is much more direct: I want to change it.

That is not necessarily rude, but in a business or formal setting it can sound too blunt.
変更させていただきたい softens the statement and shows humility.

Compare:

• 変更したいです = I want to change it
• 変更させていただきたいんですが = I would like to ask for permission to change it

This kind of phrasing is very common in business Japanese, customer service, and other polite situations.

んです adds an explanatory or softening tone.

Without it:

• 変更させていただきたいですが... sounds awkward

With it:

• 変更させていただきたいんですが... sounds natural and gentle

Here, んです helps present the speaker’s request as an explanation of their situation, rather than as a hard demand. It often makes requests and sensitive statements sound more considerate.

This が is a softening connector. It is like saying:

• ..., but...
• ..., however...

In this kind of sentence, it does not create a strong contrast. Instead, it gently leads into the actual request.

So:

• 変更させていただきたいんですが、よろしいでしょうか。

feels like:

• I’d like to ask to change it to the afternoon, and I was wondering if that would be okay.

This is a very common Japanese way to make a request sound less direct.

よろしいでしょうか is a more polite version of いいですか.

• いいですか = Is it okay?
• よろしいでしょうか = Would that be acceptable? / Would that be alright?

よろしい is a polite/formal equivalent of いい.
でしょうか also sounds softer and more refined than plain ですか.

So in a formal setting, よろしいでしょうか is much more appropriate.

Japanese often leaves out subjects and other obvious information.

In this sentence, the speaker is asking the listener for permission or acceptance regarding changing the meeting to the afternoon.

A natural interpretation is:

• I would like to have tomorrow’s meeting changed to the afternoon; would that be okay?

Depending on context, this can imply:

• the speaker wants to change the schedule themselves, or
• the speaker wants the listener to agree to the change

What matters most is that the speaker is being polite and asking for the listener’s approval.

Yes, it is natural and appropriately formal, especially in business or professional communication.

It sounds respectful and careful. That said, it is on the polite side and a little heavy, because させていただく is a very formal expression.

Some possible alternatives are:

• 明日の面談を午後に変更したいのですが、よろしいでしょうか。
  Slightly simpler, still polite.

• 明日の面談を午後に変更していただけますでしょうか。
  This sounds more like Could you change tomorrow’s meeting to the afternoon?

So the best version depends on nuance:

• 変更したい = I want to change it
• 変更させていただきたい = I would like to ask permission to change it
• 変更していただきたい = I would like you to change it

Yes. 面談 often means a face-to-face meeting, interview, consultation, or formal discussion.

Depending on context, it could be:

• a job interview
• a meeting with a teacher
• a consultation
• a scheduled one-on-one meeting

So learners often need to remember that 面談 is a bit more specific than a general meeting. It usually suggests a formal or purposeful face-to-face conversation rather than just any gathering.