buid.gradle.txt

 implementation 'com.google.mlkit:language-id:16.1.1'
 implementation 'com.google.mlkit:translate:16.1.1'

LanguageId.kt

package com.siddhantkushwaha.carolyn.ml

import com.google.android.gms.tasks.Tasks
import com.google.mlkit.nl.languageid.LanguageIdentification
import kotlin.Exception


class LanguageId {

    companion object {

        public fun getLanguage(body: String): String {
            try {
                val languageIdentifier = LanguageIdentification.getClient()
                return Tasks.await(languageIdentifier.identifyLanguage(body))
            } catch (exception: Exception) {
                exception.printStackTrace()
            }
            return "und"
        }
    }
}

LanguageTranslator.kt

package com.siddhantkushwaha.carolyn.ml

import com.google.android.gms.tasks.Tasks
import com.google.mlkit.common.model.DownloadConditions
import com.google.mlkit.common.model.RemoteModelManager
import com.google.mlkit.nl.translate.*
import com.siddhantkushwaha.carolyn.ml.LanguageId.Companion.getLanguage


class LanguageTranslator {

    companion object {

        private fun downloadModel() {
            val modelManager = RemoteModelManager.getInstance()
            val hindiToEnglishModel = TranslateRemoteModel.Builder(TranslateLanguage.HINDI).build()
            val conditions = DownloadConditions.Builder().build()
            Tasks.await(modelManager.download(hindiToEnglishModel, conditions))
        }

        private fun getTranslator(): Translator {
            val options = TranslatorOptions.Builder().setSourceLanguage(TranslateLanguage.HINDI)
                .setTargetLanguage(TranslateLanguage.ENGLISH).build()
            return Translation.getClient(options)
        }

        private fun loadModel(forceDownload: Boolean = false): Translator {
            return if (isModelDownloaded() && !forceDownload) {
                getTranslator()
            } else {
                downloadModel()
                getTranslator()
            }
        }

        public fun isModelDownloaded(): Boolean {
            val modelManager = RemoteModelManager.getInstance()
            val hindiToEnglishModel = TranslateRemoteModel.Builder(TranslateLanguage.HINDI).build()
            return Tasks.await(modelManager.isModelDownloaded(hindiToEnglishModel))
        }

        public fun translate(body: String, skipIfNotDownloaded: Boolean = true): String? {
            try {
                if (skipIfNotDownloaded && !isModelDownloaded()) {
                    return null
                }

                val language = getLanguage(body)
                if (language == "en" || language == "und")
                    return null

                val translator = loadModel()
                return Tasks.await(translator.translate(body))

            } catch (exception: Exception) {
                exception.printStackTrace()
            }
            return null
        }
    }
}