העמיתה שלי חושבת שהשיטה הזאת חיונית, אבל אני לא בטוחה שהיא רלוונטית לכולם.

העמיתה means the female colleague / the woman colleague. It is feminine because the sentence is talking about a female colleague.

• feminine: עמיתה
• masculine: עמית

With the definite article:

• העמיתה = the female colleague
• העמית = the male colleague

This also affects the verb later: חושבת is feminine because העמיתה is feminine.

In Hebrew, possession with של usually comes after the noun:

• העמיתה שלי = my colleague
• literally: the colleague of-mine

This is the normal pattern in Modern Hebrew:

• הספר שלי = my book
• המורה שלנו = our teacher

So unlike English, you usually do not put the possessive word before the noun.

Because the subject is feminine: העמיתה שלי.

In the present tense, Hebrew verbs often agree with the subject’s gender and number:

• הוא חושב = he thinks
• היא חושבת = she thinks

So:

• העמיתה שלי חושבת = my female colleague thinks

If the subject were masculine, you would say:

• העמית שלי חושב

The prefix ש־ means that in this kind of sentence. It introduces a subordinate clause.

• חושבת שהשיטה הזאת חיונית = thinks that this method is essential
• לא בטוחה שהיא רלוונטית = not sure that it is relevant

So:

• שהשיטה = that the method
• שהיא = that it / that she

In everyday Hebrew, ש־ is very common and often corresponds to English that.

In Hebrew, demonstratives like this usually come after the noun:

• השיטה הזאת = this method
• הספר הזה = this book
• הילדה הזאת = this girl

This is different from English, where this comes before the noun.

Also notice agreement:

• שיטה is feminine singular
• so the demonstrative is הזאת

Masculine singular would be:

• הספר הזה

חיונית is the feminine singular form of the adjective essential / vital.

It agrees with השיטה, which is a feminine singular noun:

• שיטה = feminine singular
• therefore חיונית = feminine singular adjective

Compare:

• השיטה חיונית = the method is essential
• הרעיון חיוני = the idea is essential (masculine noun, so masculine adjective)

Because the speaker is feminine. With אני in the present tense or with adjectives, Hebrew often shows the speaker’s gender:

• אני בטוחה = I am sure (said by a woman)
• אני בטוח = I am sure (said by a man)

So:

• אני לא בטוחה = I am not sure (female speaker)

This is very common in Hebrew and has no direct equivalent in English.

In the present tense, Hebrew usually does not use a separate verb meaning to be.

So:

• השיטה הזאת חיונית = this method is essential
• literally: this method essential
• היא רלוונטית = it is relevant
• אני לא בטוחה = I am not sure

This is completely normal Hebrew. A present-tense is/am/are is usually just understood.

היא here refers back to השיטה.

Since שיטה is a feminine noun, the pronoun used for it is the same as the pronoun for she:

• היא = she / it (for feminine nouns)

So:

• אני לא בטוחה שהיא רלוונטית לכולם = I’m not sure that it is relevant to everyone

Even though English uses it, Hebrew uses the feminine pronoun because שיטה is grammatically feminine.

Again, because it describes השיטה, which is feminine.

Hebrew adjectives agree with the noun in gender and number:

• שיטה רלוונטית = a relevant method
• נושא רלוונטי = a relevant topic (masculine)

So in שהיא רלוונטית, the adjective is feminine singular to match היא = the method.

לכולם means to everyone or for everyone, depending on context.

It is made of:

• ל־ = to / for
• כולם = everyone / all of them

So:

• רלוונטית לכולם = relevant to everyone

This is a very common structure in Hebrew:

• ברור לכולם = clear to everyone
• מתאים לכולם = suitable for everyone

Because the adjective רלוונטי/רלוונטית normally takes the preposition ל־ when you say something is relevant to someone.

So Hebrew says:

• רלוונטי לי = relevant to me
• רלוונטית לך = relevant to you
• רלוונטית לכולם = relevant to everyone

Without ל־, the sentence would not sound right.

Yes. אבל is the standard and very common word for but.

In this sentence it connects two contrasting ideas:

• העמיתה שלי חושבת...
• אבל אני לא בטוחה...

So it works just like English but.

Yes, very normal.

The sentence follows a natural Hebrew structure:

1. subject: העמיתה שלי
2. verb: חושבת
3. subordinate clause: שהשיטה הזאת חיונית
4. contrast: אבל
5. new subject: אני
6. predicate: לא בטוחה
7. subordinate clause: שהיא רלוונטית לכולם

Nothing here is unusually literary or poetic; it is standard modern Hebrew.

Yes. In modern spoken Hebrew, השיטה הזאת is the standard way to say this method.

You may also encounter:

• השיטה הזו

Both mean the same thing: this method.
הזאת is a bit fuller/formal-sounding, while זו is very common in speech and writing.

So both are correct:

• השיטה הזאת חיונית
• השיטה הזו חיונית