He was pretty popular as a political figure by the time he became president but did take criticism from both major political parties - Federalist and Democratic-Republican, while in office, as well as criticism from foreign powers.

With the off again - on again Napoleonic Wars raging in Europe, there was pressure from both political parties to take a side. If he were to ask Congress to side with France (who aided us during the War for Independence and formed an alliance with the US), we would have to stop trading with Great Britain. Federalists opposed this option because virtually all tax revenue came from tariffs during Washington's presidency and 90% of tariff revenue came from trading specifically with Great Britain. The option Federalists preferred was to join the side of Great Britain and maintain the trading relationship, but Democratic-Republicans like Jefferson and Madison believed that we owed France a debt. Washington chose neutrality, arguing that debt incurred by a war wasn't worth it and that France was strong enough to fight their own battles without help from the US, especially considering we didn't have much to offer in the 1790s anyway, with a lot of national debt and no permanent army or navy. That wasn't well received by either major political party or France or GB. His support of Hamilton's whiskey tax wasn't well received by farmers in Western Pennsylvania, leading to the Whiskey Rebellion. His bipartisan cabinet wasn't liked by politicians that identified with the major parties. His support of Hamilton's belief in a loose construction of the constitution was not well received by Democratic-Republicans that believed any action taken by the government should be specifically condoned by the constitution, instead of merely implied as a power of government by the constitution. This also led to a lot of criticism about supporting Federalist views way more often than Republican views despite being openly against the idea of forming political parties. Jefferson left the cabinet because Hamilton was a better manipulator of Washington than he was. The events leading to the Treaty of Greenville and continual westward displacement of Native American groups angered Native Americans living west of Ohio, leading to their eventual involvement in the War of 1812.

Although he is widely viewed as one of our best presidents, with a lot of careful thought going into his actions, it's not like Washington didn't have a bunch of incredibly tough choices to make. Some of the stuff on his plate was lose-lose, and he took punches for the decisions that he made for some of those things. But he is widely credited with having far more successes than failures, by setting precedents that were good for the country (that we should probably still follow today) including filling the cabinet with experts rather than political backers, serving only two terms, choosing to be treated like a civilian instead of a military officer, caring more about what's best for the country than what's best for political gain, avoiding debt whenever possible, avoiding permanent alliances with other countries so as to avoid war whenever possible (because peace is better for the budget), and making sure that a lot of faith was placed in the courts, which ultimately serves as the branch of government which protects citizens the most.