Not really. Taiwan was the best example until the adultery law was found to be unconstitutional in May 2020. Apart from that, the best current examples are Canada, where adultery is illegal in some specific cases and the US, where adultery is illegal in some states. In both countries, actual prosecutions are very rare.
Currently, twenty-eight countries have legalised same-sex marriage nationwide, with the presumption of consummation. I have summarised below when adultery was decriminalised in each case. I haven't included Mexico, as although the unions must be respected nation-wide, thanks to a Supreme Court ruling in 2010, they can't be performed nation-wide. If we do count Mexico, adultery was decriminalised in 2011, so it was only an example for a short period of time.
Netherlands - Legalised same-sex marriage April 1st, 2001. Adultery removed from the criminal code in 1971.
Belgium - Legalised same-sex marriage June 1st, 2003. Adultery decriminalised in 1987.
Spain - Legalised same-sex marriage July 3rd, 2005. Adultery decriminalised May 26th, 1978.
Canada - Legalised same-sex marriage July 20th, 2005. Adultery decriminalised partially by the UK's Matrimonial Causes Act 1857, which applied in parts of Canada, later extended to Ontario in 1930 and formally decriminalised in 1967. However, R.S.C., 1985, c. C-46 § 172(1) states:
Every one who, in the home of a child, participates in adultery or
sexual immorality or indulges in habitual drunkenness or any other
form of vice, and thereby endangers the morals of the child or renders
the home an unfit place for the child to be in, is guilty of an
indictable offence and liable to imprisonment for a term not exceeding
two years.
On the other hand, subsection (4) states:
No proceedings shall be commenced under subsection (1) without the consent of the Attorney General, unless they are instituted by or at the instance of a recognized society for the protection of children or by an officer of a juvenile court.
So adultery is only illegal in certain circumstances, and even then can only be prosecuted in particular cases.
South Africa - Legalised same-sex marriage November 30th, 2006. Adultery decriminalised by Green v Fitzgerald, 1914.
Norway - Legalised same-sex marriage January 1st, 2009. Adultery was decriminalised when the 1902 Criminal Code was repealed in 1927.
Sweden - Legalised same-sex marriage May 1st, 2009. Adultery ceased to be a crime in 1937.
Portugal - Legalised same-sex marriage June 5th, 2010. Adultery decriminalised in 1982.
Iceland - Legalised same-sex marriage June 27th, 2010. Adultery not a crime in 2010, can't find exact decriminalisation date.
Argentina - Legalised same-sex marriage July 22nd, 2010. Adultery decriminalised in 1995.
Denmark - Legalised same-sex marriage June 15th, 2012. Adultery decriminalised in 1930.
Brazil - Legalised same-sex marriage May 16th, 2013. Adultery decriminalised in 2005.
France - Legalised same-sex marriage May 18th, 2013. Adultery decriminalised in 1975.
Uruguay - Legalised same-sex marriage August 5th, 2013. Unable to find a reference for when adultery was decriminalised, however, it is not a crime currently, and was not in 2013.
New Zealand - Legalised same-sex marriage August 19th, 2013. Adultery decriminalised in 1867.
Luxembourg - Legalised same-sex marriage January 1st, 2015. Adultery decriminalised in 1974.
USA - Legalised same-sex marriage nation-wide June 26th, 2015. Adultery is still technically illegal in Arizona, Florida, Kansas, Illinois, Oklahoma, Idaho, Michigan, Wisconsin, Minnesota, New York, Mississippi, Georgia, North Carolina, South Carolina, and Maryland, although prosecutions are rare. In addition, Massachusetts and Utah only decriminalised adultery in 2018 and 2019 respectively, so they would also have been examples.
Ireland - Legalised same-sex marriage November 16th, 2015. Adultery decriminalised in 1976.
Colombia - Legalised same-sex marriage April 28th, 2016. Can't find a reference for the decriminalisation of adultery, but a law criminalising it was proposed and rejected in 2007, implying that it was legal in 2016.
Finland - Legalised same-sex marriage March 1st, 2017. Adultery decriminalised in 1948.
Malta - Legalised same-sex marriage September 1st, 2017. Adultery decriminalised in 1973.
Germany - Legalised same-sex marriage October 1st, 2017. Adultery decriminalised in then West Germany in 1969.
Australia - Legalised same-sex marriage December 9th, 2017. A federal law passed in 1994 legalised sexual activity between consenting adults and prohibited the making of laws that arbitrarily interfere with the sexual conduct of adults in private, irrespective of marital status.
Austria - Legalised same-sex marriage January 1st, 2019. Adultery decriminalised in 1997.
Taiwan - The country which motivated the question; legalised same-sex marriage May 24th, 2019. The adultery law was held unconstitutional by the Constitutional Court on May 29th, 2020, so Taiwan is no longer an example.
Ecuador - Legalised same-sex marriage July 8th, 2019. Adultery decriminalised in 1998.
United Kingdom - Legalised same-sex marriage in Northern Ireland January 13th, 2020. Same-sex marriage had been legal in England, Wales, & Scotland since 2014. Adultery was decriminalised in 1857.
Costa Rica - Legalised same-sex marriage May 26th, 2020. I can't seem to isolate when adultery was decriminalised, however, it appears in the 1880 criminal code, and is absent in the 1970 criminal code.