Damache and al-Jahani appeared at the court in Waterford, southeast Ireland, where they were remanded in custody.
The pair, who are the only two of the seven people arrested to face charges, will appear in court again on Friday, Irish state broadcaster RTE reported.
Another suspect, a Croatian man, was released without charge on Monday after six days of questioning, Irish police said, while the remaining suspects have been released without charge in recent days.
One of the women arrested was identified by a US law enforcement source as Jamie Paulin Ramirez, a 31-year-old mother from Colorado in the US
Her parents told the Reuters news agency that she had converted to Islam last year and had been lured to Europe by online extremists.
LaRose, who used the online name of "JihadJane", is believed to have spent two weeks in Ireland last September on a "fact-finding trip" before her arrest in October.
Vilks, who had a $100,000 bounty placed on his head by an al-Qaeda linked group in 2007, said he had received more death threats via the internet since the arrests were made.
The controversy started when Swedish regional daily Nerikes Allehanda published Vilks' satirical cartoon in 2007 to illustrate an editorial on the importance of freedom of expression.
The cartoon prompted protests by Muslims in the town of Oerebro, west of Stockholm, where the newspaper is based, while Egypt, Iran and Pakistan made formal complaints.
Vilks said he had received threatening phone calls from Somalia at the beginning of the year and that Saepo, the Swedish security police, had since advised him there was a heightened threat level against him.
He currently lives under police protection in Sweden.