I speak five languages and write professional content in three. Even so, during my first months publishing in English for a Western audience I felt like someone with an accent not only in speech but in thought.
It was not grammar. The grammar was fine. It was that I thought in Russian, translated and published, and it showed.
The problem with translation
Translation is not adaptation. It moves words between languages while keeping the structure of the original.
Russian and English build a thought differently. Russian text usually puts context first and the conclusion later. English usually starts with the conclusion and explains afterwards. The Russian reader is ready to wait, the English reader wants the point in the first sentence.
Translated literally, the result is grammatically correct and feels like a polite guest slightly out of rhythm. The reader senses it without articulating it, and scrolls on.
What that means in practice
The same material has to be written twice, not translated once.
First formulate the thought in the language you think best in. Then ask: if I were writing this for an English-speaking reader from the start, where would I begin, what matters most to them, which examples land without explanation? Then write it again from that angle. Slower than translation, different result.
What actually helps
Read good English writing in your niche. Not to copy style, but to absorb rhythm: how the argument is built, where the example appears, how short a paragraph is expected to be. On LinkedIn that means one to three lines and a lot of air.
Write the draft without thinking about language. Many people write slowly in a second language because they edit while writing, lose the thought and restart. Write fast, edit after. Separating production from editing works in any language.
Use AI for polish, not for writing. Asking it to improve phrasing without changing meaning saves time and removes awkward constructions. Asking it to write for you produces the average text of an average marketer instead of your voice.
Find one word instead of a description. Russian is descriptive, English is concrete. Where Russian says a person who handles sales, English says salesperson.
On sounding like yourself
The biggest trap in a second language is starting to sound correct rather than sounding like you. It happens when too much attention goes to avoiding mistakes, so you pick safe words, safe structures, a neutral tone.
Neutral tone kills a personal brand. Readers come to a specific person for a specific point of view. Imperfect English with a live thought beats perfect English about nothing.
Mistakes not worth correcting
A slight accent in text is not a flaw. A specific rhythm is not a flaw. Native speakers do not read only native speakers, they read people who say something interesting. One of the most-read authors in my niche is not a native speaker, and it is audible in how he builds sentences. It does not matter, because he says things others do not.
One practical step
Take a Russian text of yours that worked well. Do not translate it. Read it and formulate, in one sentence, what you wanted to say. Now start a new English text from that sentence. It will almost certainly beat the translation.