A:AnswerYes: https://www.tomsguide.com/us/pictures-story/1243-best-metro-pcs-phones.html
Almost all Galaxy phones support every major signalling technology and thus can be used with almost any carrier: MetroPCS and Sprint both use CDMA which the Galaxy S10+ supports via the Qualcomm Snapdragon 855 chipset.
A:AnswerYou can use any phone with any carrier as long as the platform supports it. Ie. Sim card technology etc. Now the reason the company may want you to use particular devices is because of the compability with their internal software for tracking... big data analytics. Each carrier can do what they want. Almost all have subcompanies with the same benefits. Ie. AT&T AND CRICKET (I found cricket offered the best price for the service. ), or metro pcs with tmobile.)